Rail transport - AbsoluteAstronomy.com

Rail transport is a means of conveyance of passengers and goods

Transport

Transport or transportation is the movement of people, cattle, animals and goods from one location to another. Modes of transport include air, rail, road, water, cable, pipeline, and space. The field can be divided into infrastructure, vehicles, and operations...

by way of wheeled vehicles running on rail tracks

Rail tracks

The track on a railway or railroad, also known as the permanent way, is the structure consisting of the rails, fasteners, sleepers and ballast , plus the underlying subgrade...

. In contrast to road transport

Road transport

Road transport or road transportation is transport on roads of passengers or goods. A hybrid of road transport and ship transport is the historic horse-drawn boat.-History:...

, where vehicles merely run on a prepared surface, rail vehicles are also directionally guided by the tracks they run on. Track usually consists of steel

Steel

Steel is an alloy that consists mostly of iron and has a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most common alloying material for iron, but various other alloying elements are used, such as manganese, chromium, vanadium, and tungsten...

rails installed on sleepers/ties

Railroad tie

A railroad tie/railway tie , or railway sleeper is a rectangular item used to support the rails in railroad tracks...

and ballast

Track ballast

Track ballast forms the trackbed upon which railway sleepers or railroad ties are laid. It is packed between, below, and around the ties. It is used to facilitate drainage of water, to distribute the load from the railroad ties, and also to keep down vegetation that might interfere with the track...

, on which the rolling stock

Rolling stock

Rolling stock comprises all the vehicles that move on a railway. It usually includes both powered and unpowered vehicles, for example locomotives, railroad cars, coaches and wagons...

, usually fitted with metal wheels, moves. However, other variations are also possible, such as slab track where the rails are fastened to a concrete foundation resting on a prepared subsurface.

Rolling stock in railway transport systems generally has lower frictional resistance when compared with highway vehicles, and the passenger and freight cars (carriages and wagons) can be coupled into longer trains. The operation

Rail transport operations

A railway has two major components: the rolling stock and the infrastructure .-Operation:...

is carried out by a railway company

Railway company

A railway company or railroad company is an entity that operates a railroad track and/or trains. Such a company can either be private or public...

, providing transport between train station

Train station

A train station, also called a railroad station or railway station and often shortened to just station,"Station" is commonly understood to mean "train station" unless otherwise qualified. This is evident from dictionary entries e.g...

s or freight customer facilities. Power is provided by locomotive

Locomotive

A locomotive is a railway vehicle that provides the motive power for a train. The word originates from the Latin loco – "from a place", ablative of locus, "place" + Medieval Latin motivus, "causing motion", and is a shortened form of the term locomotive engine, first used in the early 19th...

s which either draw electrical power from a railway electrification system

Railway electrification system

A railway electrification system supplies electrical energy to railway locomotives and multiple units as well as trams so that they can operate without having an on-board prime mover. There are several different electrification systems in use throughout the world...

or produce their own power, usually by diesel engine

Diesel engine

A diesel engine is an internal combustion engine that uses the heat of compression to initiate ignition to burn the fuel, which is injected into the combustion chamber...

s. Most tracks are accompanied by a signalling system. Railways are a safe land transport system when compared to other forms of transport.According to this source, railways are safest on both a per-mile and per-hour basis, whereas air transport

Aviation

Aviation is the design, development, production, operation, and use of aircraft, especially heavier-than-air aircraft. Aviation is derived from avis, the Latin word for bird.-History:...

is safe only on a per-mile basis Railway transport is capable of high levels of passenger and cargo utilization and energy efficiency, but is often less flexible and more capital

Capital (economics)

In economics, capital, capital goods, or real capital refers to already-produced durable goods used in production of goods or services. The capital goods are not significantly consumed, though they may depreciate in the production process...

-intensive than highway

Highway

A highway is any public road. In American English, the term is common and almost always designates major roads. In British English, the term designates any road open to the public. Any interconnected set of highways can be variously referred to as a "highway system", a "highway network", or a...

transport is, when lower traffic levels are considered.

The oldest, man-hauled railways date to the 6th century B.C, with Periander

Periander

Periander was the second tyrant of Corinth, Greece in the 7th century BC. He was the son of the first tyrant, Cypselus. Periander succeeded his father in 627 BC. He died in 585 BC....

, one of the Seven Sages of Greece

Seven Sages of Greece

The Seven Sages or Seven Wise Men was the title given by ancient Greek tradition to seven early 6th century BC philosophers, statesmen and law-givers who were renowned in the following centuries for their wisdom.-The Seven Sages:Traditionally, each of the seven sages represents an aspect of worldly...

, credited with its invention. With the British development of the steam engine, it was possible to construct mainline railways, which were a key component of the industrial revolution

Industrial Revolution

The Industrial Revolution was a period from the 18th to the 19th century where major changes in agriculture, manufacturing, mining, transportation, and technology had a profound effect on the social, economic and cultural conditions of the times...

. Also, railways reduced the costs of shipping, and allowed for fewer lost goods. The change from canals to railways allowed for "national markets" in which prices varied very little from city to city. Studies have shown that the invention and development of the railway in Europe was one of the most important technological inventions of the late 19th century for the United States, without which, GDP would have been lower by 7.0% in 1890. In the 1880s, electrified

Electricity

Electricity is a general term encompassing a variety of phenomena resulting from the presence and flow of electric charge. These include many easily recognizable phenomena, such as lightning, static electricity, and the flow of electrical current in an electrical wire...

trains were introduced, and also the first tramways and rapid transit systems came into being. Starting during the 1940s, the non-electrified railways in most countries had their steam locomotive

Locomotive

s replaced by diesel-electric locomotives, with the process being almost complete by 2000. During the 1960s, electrified high-speed railway system

High-speed rail

High-speed rail is a type of passenger rail transport that operates significantly faster than the normal speed of rail traffic. Specific definitions by the European Union include for upgraded track and or faster for new track, whilst in the United States, the U.S...

s were introduced in Japan

Japan

Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

and a few other countries. Other forms of guided ground transport outside the traditional railway definitions, such as monorail

Monorail

A monorail is a rail-based transportation system based on a single rail, which acts as its sole support and its guideway. The term is also used variously to describe the beam of the system, or the vehicles traveling on such a beam or track...

or maglev, have been tried but have seen limited use.

History

The history of the growth, decline and resurgence of rail transport can be divided up into several discrete periods defined by the principal means of motive power used.

Pre-steam

The earliest evidence of a railway was a 6 kilometres (3.7 mi) Diolkos

Diolkos

The Diolkos was a paved trackway near Corinth in Ancient Greece which enabled boats to be moved overland across the Isthmus of Corinth. The shortcut allowed ancient vessels to avoid the dangerous circumnavigation of the Peloponnese peninsula...

wagonway

Wagonway

Wagonways consisted of the horses, equipment and tracks used for hauling wagons, which preceded steam powered railways. The terms "plateway", "tramway" and in someplaces, "dramway" are also found.- Early developments :...

, which transported boats across the Corinth

Corinth

Corinth is a city and former municipality in Corinthia, Peloponnese, Greece. Since the 2011 local government reform it is part of the municipality Corinth, of which it is the seat and a municipal unit...

isthmus in Greece during the 6th century BC. Trucks pushed by slaves ran in grooves in limestone, which provided the track element. The Diolkos ran for over 600 years.

Railways began reappearing in Europe after the Dark Ages. The earliest known record of a railway in Europe from this period is a stained-glass window in the Minster of Freiburg im Breisgau in Germany, dating from around 1350. In 1515, Cardinal Matthäus Lang wrote a description of the Reisszug

Reisszug

The Reisszug is a private funicular railway providing goods access to the Hohensalzburg Castle at Salzburg in Austria...

, a funicular railway

Funicular

A funicular, also known as an inclined plane or cliff railway, is a cable railway in which a cable attached to a pair of tram-like vehicles on rails moves them up and down a steep slope; the ascending and descending vehicles counterbalance each other.-Operation:The basic principle of funicular...

at the Hohensalzburg Castle in Austria

Austria

Austria , officially the Republic of Austria , is a landlocked country of roughly 8.4 million people in Central Europe. It is bordered by the Czech Republic and Germany to the north, Slovakia and Hungary to the east, Slovenia and Italy to the south, and Switzerland and Liechtenstein to the...

. The line originally used wooden rails and a hemp

Hemp

Hemp is mostly used as a name for low tetrahydrocannabinol strains of the plant Cannabis sativa, of fiber and/or oilseed varieties. In modern times, hemp has been used for industrial purposes including paper, textiles, biodegradable plastics, construction, health food and fuel with modest...

haulage rope, and was operated by human or animal power. The line still exists, albeit in updated form, and is one of the oldest railways still to operate.

By 1550, narrow gauge railways with wooden rails were common in mines in Europe. By the 17th century, wooden wagonways were common in the United Kingdom for transporting coal from mines to canal wharfs for transshipment

Transshipment

Transshipment or Transhipment is the shipment of goods or containers to an intermediate destination, and then from there to yet another destination....

to boats. The world's oldest working railway, built in 1758, is the Middleton Railway

Middleton Railway

The Middleton Railway is the world's oldest continuously working railway. It was founded in 1758 and is now a heritage railway run by volunteers from The Middleton Railway Trust Ltd...

in Leeds

Leeds

Leeds is a city and metropolitan borough in West Yorkshire, England. In 2001 Leeds' main urban subdivision had a population of 443,247, while the entire city has a population of 798,800 , making it the 30th-most populous city in the European Union.Leeds is the cultural, financial and commercial...

. In 1764, the first gravity railroad

Gravity railroad

A gravity railroad or Gravity railway is a railroad on a slope that allow cars carrying minerals or passengers to coast down the slope by the force of gravity alone. The cars are then hauled back up the slope using animal power or a stationary engine and a cable, chain or one or more wide, flat...

in the United States was built in Lewiston, New York

Lewiston, New York

Lewiston is a village in Niagara County, New York, United States. The population was 2,781 at the 2000 census. The village is named after Morgan Lewis, an early 19th-century governor of New York. It is part of the Buffalo–Niagara Falls Metropolitan Statistical Area.The Village of Lewiston,...

. The first permanent tramway was the Leiper Railroad

Leiper Railroad

The Leiper Railroad was a horse drawn railroad that operated between 1810 and 1828 in what is now Nether Providence Township, Delaware County, Pennsylvania. It was replaced by the Leiper Canal, remnants of which are still visible...

in 1810.

The first iron plate rail way made with cast iron

Cast iron

Cast iron is derived from pig iron, and while it usually refers to gray iron, it also identifies a large group of ferrous alloys which solidify with a eutectic. The color of a fractured surface can be used to identify an alloy. White cast iron is named after its white surface when fractured, due...

plates on top of wooden rails, was taken into use in 1768. This allowed a variation of gauge

Rail gauge

Track gauge or rail gauge is the distance between the inner sides of the heads of the two load bearing rails that make up a single railway line. Sixty percent of the world's railways use a standard gauge of . Wider gauges are called broad gauge; smaller gauges, narrow gauge. Break-of-gauge refers...

to be used. At first only balloon loop

Balloon loop

A balloon loop or turning loop allows a rail vehicle or train to reverse direction without having to shunt or even stop. Balloon loops can be useful for passenger trains and unit freight trains, such as coal trains....

s could be used for turning, but later, movable points were taken into use that allowed for switching. From the 1790s, iron edge rails began to appear in the United Kingdom. In 1803, William Jessop

William Jessop

William Jessop was an English civil engineer, best known for his work on canals, harbours and early railways in the late 18th and early 19th centuries.-Early life:...

opened the Surrey Iron Railway

Surrey Iron Railway

The Surrey Iron Railway was a horse drawn plateway whose width approximated to a standard gauge railway that linked the former Surrey towns of Wandsworth and Croydon via Mitcham...

in south London, arguably the world's first horse-drawn public railway. The invention of the wrought iron

Wrought iron

thumb|The [[Eiffel tower]] is constructed from [[puddle iron]], a form of wrought ironWrought iron is an iron alloy with a very low carbon...

rail by John Birkinshaw

John Birkinshaw

John Birkinshaw was a 19th Century railway engineer from Bedlington, Northumberland noted for his invention of wrought iron rails in 1820. Up to this point, rail systems had used either wooden rails, which were totally incapable of supporting steam engines, or cast iron rails typically only 3 feet...

in 1820 allowed the short, brittle, and often uneven, cast iron rails to be extended to 15 feet (4.6 m) lengths. These were succeeded by steel

Steel

in 1857.

The railroad era in the United States began in 1830 when Peter Cooper’s locomotive, Tom Thumb, first steamed along 13 miles (20.9 km) of Baltimore and Ohio railroad track. In 1833 the nation’s second railroad ran 136 miles (218.9 km) from Charleston to Hamburg in South Carolina. Not until the 1850s, though, did railroads offer long distance service at reasonable rates. A journey from Philadelphia to Charleston involved eight different gauges, which meant that passengers and freight had to change trains seven times. Only at places like Bowling Green, Kentucky, the railroads were connected to one another.

Age of steam

The development of the steam engine

Steam engine

A steam engine is a heat engine that performs mechanical work using steam as its working fluid.Steam engines are external combustion engines, where the working fluid is separate from the combustion products. Non-combustion heat sources such as solar power, nuclear power or geothermal energy may be...

during the Industrial revolution

Industrial Revolution

in the United Kingdom

United Kingdom

The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

spurred ideas for mobile steam locomotive

Steam locomotive

A steam locomotive is a railway locomotive that produces its power through a steam engine. These locomotives are fueled by burning some combustible material, usually coal, wood or oil, to produce steam in a boiler, which drives the steam engine...

s that could haul trains on tracks. James Watt

James Watt

James Watt, FRS, FRSE was a Scottish inventor and mechanical engineer whose improvements to the Newcomen steam engine were fundamental to the changes brought by the Industrial Revolution in both his native Great Britain and the rest of the world.While working as an instrument maker at the...

's patented steam engines of 1769 (revised in 1782) were heavy low-pressure engines which were not suitable for use in locomotives. However, in 1804, using high-pressure steam, Richard Trevithick

Richard Trevithick

Richard Trevithick was a British inventor and mining engineer from Cornwall. His most significant success was the high pressure steam engine and he also built the first full-scale working railway steam locomotive...

demonstrated the first locomotive

Locomotive

-hauled train in Merthyr Tydfil

Merthyr Tydfil

Merthyr Tydfil is a town in Wales, with a population of about 30,000. Although once the largest town in Wales, it is now ranked as the 15th largest urban area in Wales. It also gives its name to a county borough, which has a population of around 55,000. It is located in the historic county of...

, United Kingdom. Accompanied with Andrew Vivian

Andrew Vivian

Andrew Vivian was a British mechanical engineer, inventor, and mine captain of the Dolcoath mine in Cornwall, England.In partnership with his cousin Richard Trevithick, the inventor of "high pressure" steam engines, and the entrepreneur Davis Giddy, Vivian financed the production of the first...

, it ran with mixed success, breaking some of the brittle cast-iron plates. Two years later, the first passenger horse-drawn railway was opened nearby between Swansea

Swansea

Swansea is a coastal city and county in Wales. Swansea is in the historic county boundaries of Glamorgan. Situated on the sandy South West Wales coast, the county area includes the Gower Peninsula and the Lliw uplands...

and Mumbles

Mumbles

Mumbles or The Mumbles is an area and community in Swansea, Wales which takes its name from the adjacent headland stretching into Swansea Bay...

The earliest British steam railways

In 1811, John Blenkinsop

John Blenkinsop

John Blenkinsop was an English mining engineer and an inventor of steam locomotives, who designed the first practical railway locomotive....

designed the first successful and practical railway locomotive—a rack railway

Rack railway

A rack-and-pinion railway is a railway with a toothed rack rail, usually between the running rails. The trains are fitted with one or more cog wheels or pinions that mesh with this rack rail...

worked by a steam locomotive between Middleton Colliery and Leeds

Leeds

on the Middleton Railway

Middleton Railway

The Middleton Railway is the world's oldest continuously working railway. It was founded in 1758 and is now a heritage railway run by volunteers from The Middleton Railway Trust Ltd...

. The locomotive, Salamanca, was built the following year. In 1825, George Stephenson

George Stephenson

George Stephenson was an English civil engineer and mechanical engineer who built the first public railway line in the world to use steam locomotives...

built the Locomotion
Locomotion No 1
Locomotion No. 1 is an early British steam locomotive. Built by George and Robert Stephenson's company Robert Stephenson and Company in 1825, it hauled the first train on the Stockton and Darlington Railway on 27 September 1825....

for the Stockton and Darlington Railway

Stockton and Darlington Railway

The Stockton and Darlington Railway , which opened in 1825, was the world's first publicly subscribed passenger railway. It was 26 miles long, and was built in north-eastern England between Witton Park and Stockton-on-Tees via Darlington, and connected to several collieries near Shildon...

, north east England, which was the first public steam railway in the world. In 1829, he built The Rocket
Stephenson's Rocket
Stephenson's Rocket was an early steam locomotive of 0-2-2 wheel arrangement, built in Newcastle Upon Tyne at the Forth Street Works of Robert Stephenson and Company in 1829.- Design innovations :...

which was entered in and won the Rainhill Trials

Rainhill Trials

The Rainhill Trials were an important competition in the early days of steam locomotive railways, run in October 1829 in Rainhill, Lancashire for the nearly completed Liverpool and Manchester Railway....

. This success led to Stephenson establishing his company as the pre-eminent builder of steam locomotives used on railways in the United Kingdom, the United States and much of Europe.

In 1830, the first intercity

Inter-city rail

Inter-city rail services are express passenger train services that cover longer distances than commuter or regional trains.There is no precise definition of inter-city rail. Its meaning may vary from country to country...

railway, the Liverpool and Manchester Railway

Liverpool and Manchester Railway

The Liverpool and Manchester Railway was the world's first inter-city passenger railway in which all the trains were timetabled and were hauled for most of the distance solely by steam locomotives. The line opened on 15 September 1830 and ran between the cities of Liverpool and Manchester in North...

, opened. The gauge was that used for the early wagonways and had been adopted for the Stockton and Darlington Railway. The width became known as the international standard gauge

Standard gauge

The standard gauge is a widely-used track gauge . Approximately 60% of the world's existing railway lines are built to this gauge...

, used by about 60% of the world's railways. This spurred the spread of rail transport outside the UK.

By the early 1850s Britain had over 7,000 miles of railway, 'a stunning achievment given that only twenty years had elapsed since the opening of the Liverpool and Manchester Railway.

Early railroads in the USA

Railroads (as they were known in the USA) were built on a far larger scale than those in Continental Europe, both in terms of the distances covered and also in the loading gauge

Loading gauge

A loading gauge defines the maximum height and width for railway vehicles and their loads to ensure safe passage through bridges, tunnels and other structures...

adopted which allowed for heavier locomotives and double-deck trains.

The Baltimore and Ohio

Baltimore and Ohio Railroad

The Baltimore and Ohio Railroad was one of the oldest railroads in the United States and the first common carrier railroad. It came into being mostly because the city of Baltimore wanted to compete with the newly constructed Erie Canal and another canal being proposed by Pennsylvania, which...

that opened in 1830 was the first to evolve from a single line to a network in the United States. By 1831, a steam railway connected Albany and Schenectady, New York, a distance of 16 miles, which was covered in 40 minutes.

The years between 1850 and 1890 saw phenomenal growth in the US railroad system, which at its peak constituted one third of the world's total mileage. Although the American Civil War

American Civil War

The American Civil War was a civil war fought in the United States of America. In response to the election of Abraham Lincoln as President of the United States, 11 southern slave states declared their secession from the United States and formed the Confederate States of America ; the other 25...

placed a temporary halt to major new developments the conflict did demonstrate the enormous strategic importance of railways at times of war. After the war major developments include the first elevated railway built in New York in 1867 and the symbolically important first transcontinental railway

First Transcontinental Railroad

The First Transcontinental Railroad was a railroad line built in the United States of America between 1863 and 1869 by the Central Pacific Railroad of California and the Union Pacific Railroad that connected its statutory Eastern terminus at Council Bluffs, Iowa/Omaha, Nebraska The First...

was completed in 1869.

Electrification and dieselisation

Experiments with electrical railways were started by Robert Davidson in 1838. He completed a battery-powered carriage capable of 6.4 km/h (4 mph). The Gross-Lichterfelde Tramway

Gross-Lichterfelde Tramway

The Gross Lichterfelde Tramway was the world's first electric tramway. It was built by the Siemens & Halske company in Lichterfelde, a suburb of Berlin, and went in service on 16 May 1881....

was the first to use electricity fed to the trains en-route, when it opened in 1881. Overhead wires were taken into use in the Mödling and Hinterbrühl Tram

Mödling and Hinterbrühl Tram

Mödling and Hinterbrühl Tram or Mödling and Hinterbrühl Local Railway was an electric tramway in Austria, running from Mödling to Hinterbrühl, in the southwest of Vienna. The gauge was 1000 mm...

in Austria in October 1883. At first, this was taken into use on tram

Tram

A tram is a passenger rail vehicle which runs on tracks along public urban streets and also sometimes on separate rights of way. It may also run between cities and/or towns , and/or partially grade separated even in the cities...

ways that, until then, had been horse-drawn tram

Tram

cars. The first conventional completely electrified railway mainline was the 106 km Valtellina

Valtellina

Valtellina or the Valtelline valley ; is a valley in the Lombardy region of northern Italy, bordering Switzerland. Today it is known for its skiing, its hot spring spas, its cheeses and its wines...

line in Italy that was opened on 4 September 1902. During the 1890s, many large cities, such as London

London Underground

The London Underground is a rapid transit system serving a large part of Greater London and some parts of Buckinghamshire, Hertfordshire and Essex in England...

, Paris

Paris Métro

The Paris Métro or Métropolitain is the rapid transit metro system in Paris, France. It has become a symbol of the city, noted for its density within the city limits and its uniform architecture influenced by Art Nouveau. The network's sixteen lines are mostly underground and run to 214 km ...

and New York used the new technology to build rapid transit

Rapid transit

A rapid transit, underground, subway, elevated railway, metro or metropolitan railway system is an electric passenger railway in an urban area with a high capacity and frequency, and grade separation from other traffic. Rapid transit systems are typically located either in underground tunnels or on...

for urban commuting. In smaller cities, tramways became common and were often the only mode of public transport

Public transport

Public transport is a shared passenger transportation service which is available for use by the general public, as distinct from modes such as taxicab, car pooling or hired buses which are not shared by strangers without private arrangement.Public transport modes include buses, trolleybuses, trams...

until the introduction of buses in the 1920s. In North America, interurban

Interurban

An interurban, also called a radial railway in parts of Canada, is a type of electric passenger railroad; in short a hybrid between tram and train. Interurbans enjoyed widespread popularity in the first three decades of the twentieth century in North America. Until the early 1920s, most roads were...

s became a common mode to reach suburban areas. At first, all electric railways used direct current

Direct current

Direct current is the unidirectional flow of electric charge. Direct current is produced by such sources as batteries, thermocouples, solar cells, and commutator-type electric machines of the dynamo type. Direct current may flow in a conductor such as a wire, but can also flow through...

but, in 1904, the Stubaital Line in Austria opened with alternating current

Alternating current

In alternating current the movement of electric charge periodically reverses direction. In direct current , the flow of electric charge is only in one direction....

.

Steam locomotives require large pools of labour to clean, load, maintain and run. After World War II

World War II

World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

, dramatically increased labour costs in developed countries made steam an increasingly costly form of motive power. At the same time, the war had forced improvements in internal combustion engine technology that made diesel locomotives cheaper and more powerful. This caused many railway companies to initiate programmes to convert all unelectrified sections from steam to diesel locomotion

Diesel locomotive

A diesel locomotive is a type of railroad locomotive in which the prime mover is a diesel engine, a reciprocating engine operating on the Diesel cycle as invented by Dr. Rudolf Diesel...

.

Following the large-scale construction of motorways after the war, rail transport became less popular for commuting and air transport started taking large market shares from long-haul passenger trains. Most tramways were either replaced by rapid transits or buses, while high transshipment costs caused short-haul freight trains to become uncompetitive. The 1973 oil crisis

1973 oil crisis

The 1973 oil crisis started in October 1973, when the members of Organization of Arab Petroleum Exporting Countries or the OAPEC proclaimed an oil embargo. This was "in response to the U.S. decision to re-supply the Israeli military" during the Yom Kippur war. It lasted until March 1974. With the...

led to a change of mind set and most tram systems that had survived into the 1970s remain today. At the same time, containerization

Containerization

Containerization is a system of freight transport based on a range of steel intermodal containers...

allowed freight trains to become more competitive and participate in intermodal freight transport

Intermodal freight transport

Intermodal freight transport involves the transportation of freight in an intermodal container or vehicle, using multiple modes of transportation , without any handling of the freight itself when changing modes. The method reduces cargo handling, and so improves security, reduces damages and...

. With the 1964 introduction of the Shinkansen

Shinkansen

The , also known as THE BULLET TRAIN, is a network of high-speed railway lines in Japan operated by four Japan Railways Group companies. Starting with the Tōkaidō Shinkansen in 1964, the network has expanded to currently consist of of lines with maximum speeds of , of Mini-shinkansen with a...

high-speed rail

High-speed rail

in Japan, trains could again have a dominant position on intercity travel. During the 1970s, the introduction of automated rapid transit systems allowed cheaper operation. The 1990s saw an increased focus on accessibility

Accessibility

Accessibility is a general term used to describe the degree to which a product, device, service, or environment is available to as many people as possible. Accessibility can be viewed as the "ability to access" and benefit from some system or entity...

and low-floor trains. Many tramways have been upgraded to light rail

Light rail

Light rail or light rail transit is a form of urban rail public transportation that generally has a lower capacity and lower speed than heavy rail and metro systems, but higher capacity and higher speed than traditional street-running tram systems...

and many cities that closed their old tramways have reopened new light railway systems.

Innovations

Many benchmarks in equipment and infrastructure led to the growing use of railways. Some innovative features taking place in the 19th and 20th centuries included wood cars replaced with all-steel cars, which provided better safety and maintenance; iron

Iron

Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...

rails replaced with steel

Steel

rails, which provided higher speed and capacity with lower weight and cost; stove-heated cars to steam-heating cars, piped from locomotive; gas lighting

Gas lighting

Gas lighting is production of artificial light from combustion of a gaseous fuel, including hydrogen, methane, carbon monoxide, propane, butane, acetylene, ethylene, or natural gas. Before electricity became sufficiently widespread and economical to allow for general public use, gas was the most...

to electric lighting, with use of battery

Battery (electricity)

An electrical battery is one or more electrochemical cells that convert stored chemical energy into electrical energy. Since the invention of the first battery in 1800 by Alessandro Volta and especially since the technically improved Daniell cell in 1836, batteries have become a common power...

/alternator

Alternator

An alternator is an electromechanical device that converts mechanical energy to electrical energy in the form of alternating current.Most alternators use a rotating magnetic field but linear alternators are occasionally used...

unit beneath the car; development of air-conditioning with additional underbody equipment and ice compartment. Some innovative rolling stock included the lightweight, diesel-powered streamliner

Streamliner

A streamliner is a vehicle incorporating streamlining in a shape providing reduced air resistance. The term is applied to high-speed railway trainsets of the 1930s to 1950s, and to their successor "bullet trains". Less commonly, the term is applied to fully faired recumbent bicycles...

, which was an modernistic, aerodynamically-styled train with flowing contours; then came the ultra-lightweight car with internal combustion engine

Internal combustion engine

The internal combustion engine is an engine in which the combustion of a fuel occurs with an oxidizer in a combustion chamber. In an internal combustion engine, the expansion of the high-temperature and high -pressure gases produced by combustion apply direct force to some component of the engine...

in each train's power car; others included the dome car, turbined-powered trains, bilevel rolling stock, and the high-tech/high-speed electric trains.

Even more, in the first half of the 20th century, infrastructure elements adopted technological changes including the continuously welded rail that was 1/4 miles long; concrete tie usage; double tracking major lines; intermodal terminal and handling technology; advances in diesel-electric propulsion to include AC

AC or Ac may refer to:* Air conditioning, the mechanical process of cooling air in enclosed spaces* Air conditioner, a machine that produces cool air* Anarcho-capitalism, a form of free-market anarchism...

traction systems and propulsion braking systems; and just-in-time inventory control. Beyond technology, even management of systems seen improvements with the adoption of environmental impact concerns; heightened concern of employee and public safety

Public Safety

Public safety involves the prevention of and protection from events that could endanger the safety of the general public from significant danger, injury/harm, or damage, such as crimes or disasters .-See also:* By nation...

; introduction of urban area

Urban area

An urban area is characterized by higher population density and vast human features in comparison to areas surrounding it. Urban areas may be cities, towns or conurbations, but the term is not commonly extended to rural settlements such as villages and hamlets.Urban areas are created and further...

rail networks and public agencies to manage them; and downsizing of the industry employment with greater use of contractors and consultants.

Trains

A train is a connected series of rail vehicles that move along the track. Propulsion for the train is provided by a separate locomotive or from individual motors in self-propelled multiple units. Most trains carry a revenue load, although non-revenue cars exist for the railway's own use, such as for maintenance-of-way purposes. The engine driver

Railroad engineer

A railroad engineer, locomotive engineer, train operator, train driver or engine driver is a person who drives a train on a railroad...

controls the locomotive or other power cars, although people mover

People mover

A people mover or automated people mover is a fully automated, grade-separated mass transit system.The term is generally used only to describe systems serving relatively small areas such as airports, downtown districts or theme parks, but is sometimes applied to considerably more complex automated...

s and some rapid transits are driverless.

Haulage

Traditionally, trains are pulled using a locomotive. This involved a single or multiple powered vehicles being located at the front of the train and providing sufficient adhesion to haul the weight of the full train. This remains dominant for freight trains and is often used for passenger trains. A push-pull train

Push-pull train

Push–pull is a mode of operation for locomotive-hauled trains allowing them to be driven from either end.A push–pull train has a locomotive at one end of the train, connected via some form of remote control, such as multiple-unit train control, to a vehicle equipped with a control cab at the other...

has the end passenger car equipped with a driver's cab so the engine driver can remotely control the locomotive. This allows one of the locomotive-hauled trains drawbacks to be removed, since the locomotive need not be moved to the end of the train each time the train changes direction. A railroad car

Railroad car

A railroad car or railway vehicle , also known as a bogie in Indian English, is a vehicle on a rail transport system that is used for the carrying of cargo or passengers. Cars can be coupled together into a train and hauled by one or more locomotives...

is a vehicle used for the haulage of either passengers or freight.

A multiple unit has powered wheels throughout the whole train. These are used for rapid transit and tram systems, as well as many both short- and long-haul passenger trains. A railcar

Railcar

A railcar, in British English and Australian English, is a self-propelled railway vehicle designed to transport passengers. The term "railcar" is usually used in reference to a train consisting of a single coach , with a driver's cab at one or both ends. Some railways, e.g., the Great Western...

is a single, self-powered car. Multiple units have a driver's cab at each end of the unit and were developed following the ability to build electric motor

Electric motor

An electric motor converts electrical energy into mechanical energy.Most electric motors operate through the interaction of magnetic fields and current-carrying conductors to generate force...

s and engine

Engine

An engine or motor is a machine designed to convert energy into useful mechanical motion. Heat engines, including internal combustion engines and external combustion engines burn a fuel to create heat which is then used to create motion...

s small enough to build under the coach. There are only a few freight multiple units, most of which are high-speed post trains.

Motive power

Steam locomotive

s are locomotives with a steam engine

Steam engine

that provides adhesion. Coal

Coal

Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers or veins called coal beds or coal seams. The harder forms, such as anthracite coal, can be regarded as metamorphic rock because of later exposure to elevated temperature and pressure...

, petroleum

Petroleum

Petroleum or crude oil is a naturally occurring, flammable liquid consisting of a complex mixture of hydrocarbons of various molecular weights and other liquid organic compounds, that are found in geologic formations beneath the Earth's surface. Petroleum is recovered mostly through oil drilling...

, or wood

Wood

Wood is a hard, fibrous tissue found in many trees. It has been used for hundreds of thousands of years for both fuel and as a construction material. It is an organic material, a natural composite of cellulose fibers embedded in a matrix of lignin which resists compression...

is burned in a firebox. The heat boils water in the fire-tube boiler

Fire-tube boiler

A fire-tube boiler is a type of boiler in which hot gases from a fire pass through one or more tubes running through a sealed container of water...

to create pressurized steam. The steam travels through the smokebox

Smokebox

A smokebox is one of the major basic parts of a Steam locomotive exhaust system. Smoke and hot gases pass from the firebox through tubes where they pass heat to the surrounding water in the boiler. The smoke then enters the smokebox, and is exhausted to the atmosphere through the chimney .To assist...

before leaving via the chimney. In the process, it powers a piston

Piston

A piston is a component of reciprocating engines, reciprocating pumps, gas compressors and pneumatic cylinders, among other similar mechanisms. It is the moving component that is contained by a cylinder and is made gas-tight by piston rings. In an engine, its purpose is to transfer force from...

that transmits power directly through a connecting rod

Connecting rod

In a reciprocating piston engine, the connecting rod or conrod connects the piston to the crank or crankshaft. Together with the crank, they form a simple mechanism that converts linear motion into rotating motion....

(US: main rod) and a crankpin (US: wristpin) on the driving wheel

Driving wheel

On a steam locomotive, a driving wheel is a powered wheel which is driven by the locomotive's pistons...

(US main driver) or to a crank

Crankshaft

The crankshaft, sometimes casually abbreviated to crank, is the part of an engine which translates reciprocating linear piston motion into rotation...

on a driving axle. Steam locomotives have been phased out in most parts of the world for economical and safety reasons although many are preserved in working order by heritage railway

Heritage railway

thumb|right|the Historical [[Khyber train safari|Khyber Railway]] goes through the [[Khyber Pass]], [[Pakistan]]A heritage railway , preserved railway , tourist railway , or tourist railroad is a railway that is run as a tourist attraction, in some cases by volunteers, and...

s.

Electric locomotive

Electric locomotive

An electric locomotive is a locomotive powered by electricity from overhead lines, a third rail or an on-board energy storage device...

s draw power from a stationary source via an overhead wire

Overhead lines

Overhead lines or overhead wires are used to transmit electrical energy to trams, trolleybuses or trains at a distance from the energy supply point...

or third rail

Third rail

A third rail is a method of providing electric power to a railway train, through a semi-continuous rigid conductor placed alongside or between the rails of a railway track. It is used typically in a mass transit or rapid transit system, which has alignments in its own corridors, fully or almost...

. Some also or instead use a battery. A transformer

Transformer

A transformer is a device that transfers electrical energy from one circuit to another through inductively coupled conductors—the transformer's coils. A varying current in the first or primary winding creates a varying magnetic flux in the transformer's core and thus a varying magnetic field...

in the locomotive converts the high voltage, low current power to low voltage, high current used in the electric motor

Electric motor

An electric motor converts electrical energy into mechanical energy.Most electric motors operate through the interaction of magnetic fields and current-carrying conductors to generate force...

s that power the wheels. Modern locomotives use three-phase AC induction motors. Electric locomotives are the most powerful traction. They are also the cheapest to run and provide less noise and no local air pollution. However, they require high capital investments both for the overhead lines

Overhead lines

Overhead lines or overhead wires are used to transmit electrical energy to trams, trolleybuses or trains at a distance from the energy supply point...

and the supporting infrastructure. Accordingly, electric traction is used on urban systems, lines with high traffic and for high-speed rail.

Diesel locomotive

Diesel locomotive

A diesel locomotive is a type of railroad locomotive in which the prime mover is a diesel engine, a reciprocating engine operating on the Diesel cycle as invented by Dr. Rudolf Diesel...

s use a diesel engine

Diesel engine

A diesel engine is an internal combustion engine that uses the heat of compression to initiate ignition to burn the fuel, which is injected into the combustion chamber...

as the prime mover

Prime mover (locomotive)

In engineering, a prime mover is an engine that converts fuel to useful work. In locomotives, the prime mover is thus the source of power for its propulsion. The term is generally used when discussing any locomotive powered by an internal combustion engine...

. The energy transmission may be either diesel-electric, diesel-mechanical or diesel-hydraulic but diesel-electric is dominant. Electro-diesel locomotive

Electro-diesel locomotive

An Electro-diesel locomotive is powered either from an electricity supply or by using the onboard diesel engine...

s are built to run as diesel-electric on unelectrified sections and as electric locomotives on electrified sections.

Alternative methods of motive power include magnetic levitation, horse-drawn, cable

Funicular

, gravity, pneumatics

Pneumatics

Pneumatics is a branch of technology, which deals with the study and application of use of pressurized gas to effect mechanical motion.Pneumatic systems are extensively used in industry, where factories are commonly plumbed with compressed air or compressed inert gases...

and gas turbine

Gas turbine

A gas turbine, also called a combustion turbine, is a type of internal combustion engine. It has an upstream rotating compressor coupled to a downstream turbine, and a combustion chamber in-between....

Passenger trains

A passenger train travels between stations where passengers may embark and disembark. The oversight of the train is the duty of a guard/train manager

Conductor (transportation)

A conductor is a member of a railway train's crew that is responsible for operational and safety duties that do not involve the actual operation of the train. The title of conductor is most associated with railway operations in North America, but the role of conductor is common to railways...

. Passenger trains are part of public transport and often make up the stem of the service, with buses feeding to stations. Passenger trains can involve a variety of functions including long distance intercity travel, daily commuter trips, or local urban transit services. They even include a diversity of vehicles, operating speeds, right of way requirements, and service frequency. Passenger trains usually can be divided into two operations: intercity railway and intracity transit. Whereas as intercity railway involve higher speeds, longer routes, and lower frequency (usually scheduled), intracity transit involves lower speeds, shorter routes, and higher frequency (especially during peak hours).

Intercity trains

Inter-city rail

are long-haul trains that operate with few stops between cities. Trains typically have amenities such as a dining car

Dining car

A dining car or restaurant carriage , also diner, is a railroad passenger car that serves meals in the manner of a full-service, sit-down restaurant....

. Some lines also provide over-night services with sleeping car

Sleeping car

The sleeping car or sleeper is a railway/railroad passenger car that can accommodate all its passengers in beds of one kind or another, primarily for the purpose of making nighttime travel more restful. The first such cars saw sporadic use on American railroads in the 1830s and could be configured...

s. Some long-haul trains been given a specific name. Regional trains

Regional rail

Commuter rail, also called suburban rail, is a passenger rail transport service that primarily operates between a city center, and the middle to outer suburbs beyond 15km and commuter towns or other locations that draw large numbers of commuters—people who travel on a daily basis...

are medium distance trains that connect cities with outlying, surrounding areas, or provide a regional service, making more stops and having lower speeds. Commuter trains serve suburbs of urban areas, providing a daily commuting

Commuting

Commuting is regular travel between one's place of residence and place of work or full time study. It sometimes refers to any regular or often repeated traveling between locations when not work related.- History :...

service. Airport rail link

Airport rail link

An airport rail link is a service providing passenger rail transport from an airport to a nearby city; by mainline- or commuter trains, rapid transit, people mover or light rail...

s provide quick access from city centres to airport

Airport

An airport is a location where aircraft such as fixed-wing aircraft, helicopters, and blimps take off and land. Aircraft may be stored or maintained at an airport...

s.

High-speed rail

High-speed rail

are special inter-city trains that operates at much higher speeds than conventional railways, the limit being regarded at 200 to 320 km/h. High-speed trains are used mostly for long-haul service and most systems are in Western Europe and East Asia. The speed record

Land speed record for railed vehicles

Determination of the fastest rail vehicle in the world varies depending on the definition of "rail".Official absolute world record for conventional train is held by the French TGV...

is 574.8 km/h (357.2 mph), set by a modified French TGV

TGV

The TGV is France's high-speed rail service, currently operated by SNCF Voyages, the long-distance rail branch of SNCF, the French national rail operator....

. Magnetic levitation trains such as the Shanghai airport train use under-riding magnets which attract themselves upward towards the underside of a guideway and this line has achieved somewhat higher peak speeds in day-to-day operation than conventional high-speed railways, although only over short distances. Due to their heightened speeds, route alignments for high-speed rail tend to be steeper grades and broader curves compared to conventional railways. Their high kinetic energy translates to higher horsepower-to-ton ratios (20 hp/ton); this allows trains to accelerate and maintain higher speeds and negotiate steep grades as momentum builds up and recovered in downgrades (reducing cut, fill, and tunneling requirements). Since lateral forces act on curves, curvatures are designed with the highest possible radius. All these features are dramatically different from freight operations, thus justifying exclusive high-speed rail lines if it is economically feasible.

Rapid transit

Rapid transit

is an intracity system built in large cities and has the highest capacity of any passenger transport system. It is grade separated and commonly built underground or elevated. At street level, smaller tram

Tram

s can be used. Light rail

Light rail

s are upgraded trams that have step-free access, their own right-of-way and sometimes sections underground. Monorail

Monorail

systems operate as elevated, medium capacity systems. A people mover

People mover

is a driverless, grade-separated train that serves only a few stations, as a shuttle. Due to the wide variety of rapid transit systems without much uniformity, route alignment vary widely with diverse right-of-ways (private land, side of road, street median) and geometric characteristics (sharp or broad curves, steep or gentle grades). For instance, the Chicago El trains are designed with extremely short cars to negotiate the sharp curves in the Loop

Loop

- Technology :*Loop , sending a signal on a channel and receiving it back at the sending terminal*Loop , a method of control flow in computer science*Loop device, a Unix device node that allows a file to be mounted on a directory...

. NJ's PATH

Path

Path, pathway or PATH may refer to:-Path:* Course , the intended path of a vehicle over the surface of the Earth* Trail, hiking trail, footpath, or bridle path...

have similar-sized cars to accommodate curves in the trans-Hudson tunnels. San Francisco's BART operate large cars on its well-engineered routes.

Freight train

A freight train hauls cargo

Cargo

Cargo is goods or produce transported, generally for commercial gain, by ship, aircraft, train, van or truck. In modern times, containers are used in most intermodal long-haul cargo transport.-Marine:...

using freight car

Goods wagon

Goods wagons are railway wagons that are used for the transportation of goods .- Development :At the beginning of the railway era, the vast majority of goods wagons were four-wheeled vehicles of simple construction. These were almost exclusively small covered wagons, open wagons with side-boards,...

s specialized for the type of goods. Freight trains are very efficient, with economy of scale and high energy efficiency. However, their use can be reduced by lack of flexibility, if there is need of transshipment at both ends of the trip due to lack of tracks to the points of pick-up and delivery. Authorities often encourage the use of cargo rail transport due to its environmental profile.

Container trains

Containerization

Containerization is a system of freight transport based on a range of steel intermodal containers...

have become the dominant type in the US for non-bulk haulage. Containers can easily be transshipped to other modes, such as ships and trucks, using cranes. This has succeeded the boxcar

Boxcar

A boxcar is a railroad car that is enclosed and generally used to carry general freight. The boxcar, while not the simplest freight car design, is probably the most versatile, since it can carry most loads...

(wagon-load), where the cargo had to be loaded and unloaded into the train manually. The intermodal containerization

Containerization

Containerization is a system of freight transport based on a range of steel intermodal containers...

of cargo has revolutionized the supply chain

Supply chain

A supply chain is a system of organizations, people, technology, activities, information and resources involved in moving a product or service from supplier to customer. Supply chain activities transform natural resources, raw materials and components into a finished product that is delivered to...

logistics

Logistics

Logistics is the management of the flow of goods between the point of origin and the point of destination in order to meet the requirements of customers or corporations. Logistics involves the integration of information, transportation, inventory, warehousing, material handling, and packaging, and...

industry, reducing ship costs significantly. In Europe, the sliding wall wagon has largely superseded the ordinary covered wagons. Other types of cars include refrigerator car

Refrigerator car

A refrigerator car is a refrigerated boxcar , a piece of railroad rolling stock designed to carry perishable freight at specific temperatures. Refrigerator cars differ from simple insulated boxcars and ventilated boxcars , neither of which are fitted with cooling apparatus...

s, stock cars

Stock car (rail)

In railroad terminology, a stock car or cattle wagon is a type of rolling stock used for carrying livestock to market...

for livestock and autorack

Autorack

An autorack, also known as an auto carrier, is a specialized piece of railroad rolling stock used to transport automobiles and light trucks, generally from factories to automotive distributors...

s for road vehicles. When rail is combined with road transport, a roadrailer

Roadrailer

In railroad terminology a Roadrailer or RoadRailer is a highway trailer, or semi-trailer, that is specially equipped for use in railroad intermodal service.- Overview :...

will allow trailer

Semi-trailer

A semi-trailer is a trailer without a front axle. A large proportion of its weight is supported by a road tractor, a detachable front axle assembly known as a dolly, or the tail of another trailer...

s to be driven onto the train, allowing for easy transition between road and rail.

Bulk handling

Bulk material handling

Bulk material handling is an engineering field that is centered around the design of equipment used for the handling of dry materials such as ores, coal, cereals, wood chips, sand, gravel and stone in loose bulk form...

represents a key advantage for rail transport. Low or even zero transshipment costs combined with energy efficiency and low inventory costs allow trains to handle bulk

Bulk cargo

Bulk cargo is commodity cargo that is transported unpackaged in large quantities. This cargo is usually dropped or poured, with a spout or shovel bucket, as a liquid or as a mass of relatively small solids , into a bulk carrier ship's hold, railroad car, or tanker truck/trailer/semi-trailer body...

much cheaper than by road. Typical bulk cargo includes coal, ore, grains and liquids. Bulk is transported in open-topped car

Gondola (rail)

In railroad terminology, a gondola is an open-top type of rolling stock that is used for carrying loose bulk materials. Because of its low side walls, gondolas are used to carry either very dense material, such as steel plates or coils, or bulky items such as prefabricated pieces of rail...

s, hopper car

Hopper car

A hopper car is a type of railroad freight car used to transport loose bulk commodities such as coal, ore, grain, track ballast, and the like. The name originated from the coke manufacturing industry which is part of the steel industry ....

s and tank car

Tank car

A tank car is a type of railroad rolling stock designed to transport liquid and gaseous commodities.-Timeline:...

Infrastructure

Right of way

Railway tracks are laid upon land owned or leased by the railway company. Owing to the desirability of maintaining modest grades, rails will often be laid in circuitous routes in hilly or mountainous terrain. Route length and grade requirements can be reduced by the use of alternating cuttings, bridges and tunnels—all of which can greatly increase the capital expenditures required to develop a right of way, while significantly reducing operating costs and allowing higher speeds on longer radius curves. In densely urbanized areas, railways are sometimes laid in tunnels to minimize the effects on existing properties.

Trackage

Track consists of two parallel steel rails, anchored perpendicular

Perpendicular

In geometry, two lines or planes are considered perpendicular to each other if they form congruent adjacent angles . The term may be used as a noun or adjective...

to members called ties

Railroad tie

A railroad tie/railway tie , or railway sleeper is a rectangular item used to support the rails in railroad tracks...

(sleepers) of timber, concrete, steel, or plastic to maintain a consistent distance apart, or rail gauge

Rail gauge

. Rail gauges are usually categorised as Standard gauge

Standard gauge

The standard gauge is a widely-used track gauge . Approximately 60% of the world's existing railway lines are built to this gauge...

used on approximately 60% of the world's existing railway lines, Broad gauge

Broad gauge

Broad-gauge railways use a track gauge greater than the standard gauge of .- List :For list see: List of broad gauges, by gauge and country- History :...

and Narrow gauge

Narrow gauge

A narrow gauge railway is a railway that has a track gauge narrower than the of standard gauge railways. Most existing narrow gauge railways have gauges of between and .- Overview :...

. In addition to the rail gauge, the tracks will be laid to conform with a Loading gauge

Loading gauge

A loading gauge defines the maximum height and width for railway vehicles and their loads to ensure safe passage through bridges, tunnels and other structures...

which defines the maximum height and width for railway vehicles and their loads to ensure safe passage through bridges, tunnels and other structures.

The track guides the conical, flanged wheels, keeping the cars on the track without active steering and therefore allowing trains to be much longer than road vehicles. The rails and ties are usually placed on a foundation made of compressed earth on top of which is placed a bed of ballast

Track ballast

to distribute the load from the ties and to prevent the track from buckling

Buckling

In science, buckling is a mathematical instability, leading to a failure mode.Theoretically, buckling is caused by a bifurcation in the solution to the equations of static equilibrium...

as the ground settles over time under the weight of the vehicles passing above.

The ballast also serves as a means of drainage. Some more modern track in special areas is attached by direct fixation without ballast. Track may be prefabricated or assembled in place. By welding rails together to form lengths of continuous welded rail, additional wear and tear on rolling stock caused by the small surface gap at the joints between rails can be counteracted; this also makes for a quieter ride (passenger trains).

On curves the outer rail may be at a higher level than the inner rail. This is called superelevation or cant

Cant (road/rail)

The cant of a railway track or a road is the difference in elevation between the two edges...

. This reduces the forces tending to displace the track and makes for a more comfortable ride for standing livestock and standing or seated passengers. A given amount of superelevation will be the most effective over a limited range of speeds.

Turnouts

Railroad switch

A railroad switch, turnout or [set of] points is a mechanical installation enabling railway trains to be guided from one track to another at a railway junction....

, also known as points and switches, are the means of directing a train onto a diverging section of track. Laid similar to normal track, a point typically consists of a frog (common crossing), check rails and two switch rails. The switch rails may be moved left or right, under the control of the signalling system, to determine which path the train will follow.

Spikes in wooden ties can loosen over time, but split and rotten ties may be individually replaced with new wooden ties or concrete substitutes. Concrete ties can also develop cracks or splits, and can also be replaced individually. Should the rails settle due to soil subsidence, they can be lifted by specialized machinery and additional ballast tamped under the ties to level the rails.

Periodically, ballast must be removed and replaced with clean ballast to ensure adequate drainage. Culverts and other passages for water must be kept clear lest water is impounded by the trackbed, causing landslips. Where trackbeds are placed along rivers, additional protection is usually placed to prevent streambank erosion during times of high water. Bridges require inspection and maintenance, since they are subject to large surges of stress in a short period of time when a heavy train crosses.

Train Inspection Systems

The inspection of railway equipment is essential for the safe movement of trains. Many types of defect detector

Defect detector

A defect detector is a device used on railroads to detect axle and signal problems in passing trains. The detectors are normally integrated into the tracks and often include sensors to detect several different kinds of problems that could occur...

s are in use on the world's railroads. These devices utilize technologies vary from a simplistic paddle and switch to infrared

Infrared

Infrared light is electromagnetic radiation with a wavelength longer than that of visible light, measured from the nominal edge of visible red light at 0.74 micrometres , and extending conventionally to 300 µm...

and laser scanning, and even ultrasonic audio analysis. Their use has avoided many rail accidents over the 70 years they have been used.

Signalling

Railway signalling is a system used to control railway traffic safely to prevent trains from colliding. Being guided by fixed rails

Rail tracks

The track on a railway or railroad, also known as the permanent way, is the structure consisting of the rails, fasteners, sleepers and ballast , plus the underlying subgrade...

with low friction, trains are uniquely susceptible to collision since they frequently operate at speeds that do not enable them to stop quickly or within the driver's sighting distance. Most forms of train control involve movement authority being passed from those responsible for each section of a rail network to the train crew. Not all methods require the use of signals, and some systems are specific to single track

Single track (rail)

A single track railway is where trains in both directions share the same track. Single track is normally used on lesser used rail lines, often branch lines, where the traffic density is not high enough to justify the cost of building double tracks....

railways.

The signalling process is traditionally carried out in a signal box

Signal box

On a rail transport system, signalling control is the process by which control is exercised over train movements by way of railway signals and block systems to ensure that trains operate safely, over the correct route and to the proper timetable...

, a small building that houses the lever frame

Lever frame

Mechanical railway signalling installations rely on lever frames for their operation to interlock the signals and points to allow the safe operation of trains in the area the signals control...

required for the signalman to operate switches and signal equipment. These are placed at various intervals along the route of a railway, controlling specified sections of track. More recent technological developments have made such operational doctrine superfluous, with the centralization of signalling operations to regional control rooms. This has been facilitated by the increased use of computers, allowing vast sections of track to be monitored from a single location. The common method of block signalling divides the track into zones guarded by combinations of block signals, operating rules, and automatic-control devices so that only one train may be in a block at any time.

Electrification

The electrification system provides electrical energy to the trains, so they can operate without a prime mover onboard. This allows lower operating costs, but requires large capital investments along the lines. Mainline and tram systems normally have overhead wires, which hang from poles along the line. Grade-separated rapid transit sometimes use a ground third rail

Third rail

.

Power may be fed as direct

Direct current

or alternating current

Alternating current

In alternating current the movement of electric charge periodically reverses direction. In direct current , the flow of electric charge is only in one direction....

. The most common DC voltages are 600 and 750 V for tram and rapid transit systems, and 1,500 and 3,000 V for mainlines. The two dominant AC systems are 15 kV AC

15 kV AC

The AC railway electrification system is used in Germany, Austria, Switzerland, Sweden and Norway. The high voltage enables high power transmission with low losses powering traction motors available since the beginning of the 20th century...

and 25 kV AC

25 kV AC

The 25 kV Alternating current railway electrification system is commonly used in railways worldwide, especially for high-speed rail.-Overview:This electrification system is ideal for railways that cover long distances and/or carry heavy traffic...

Stations

A railway station serves as an area where passengers can board and alight from trains. A goods station

Goods station

A goods station is, in the widest sense, a railway station which is exclusively or predominantly where goods of any description are loaded or unloaded from ships or road vehicles and/or where goods wagons are transferred to local sidings.A station where goods are not specifically received or...

is a yard which is exclusively used for loading and unloading cargo. Large passenger stations have at least one building providing conveniences for passengers, such as purchasing tickets and food. Smaller stations typically only consist of a platform

Railway platform

A railway platform is a section of pathway, alongside rail tracks at a train station, metro station or tram stop, at which passengers may board or alight from trains or trams. Almost all stations for rail transport have some form of platforms, with larger stations having multiple platforms...

. Early stations were sometimes built with both passenger and goods facilities.

Platforms are used to allow easy access to the trains, and are connected to each other via underpasses, footbridge

Footbridge

A footbridge or pedestrian bridge is a bridge designed for pedestrians and in some cases cyclists, animal traffic and horse riders, rather than vehicular traffic. Footbridges complement the landscape and can be used decoratively to visually link two distinct areas or to signal a transaction...

and level crossings. Some large stations are built as cul-de-sac

Cul-de-sac

A cul-de-sac is a word of French origin referring to a dead end, close, no through road or court meaning dead-end street with only one inlet/outlet...

, with trains only operating out from one direction. Smaller stations normally serve local residential areas, and may have connection to feeder bus services. Large stations, in particular central station

Central station

A central station usually designates the principal passenger railway station of cities which have multiple stations. The central station functions as the main transport hub for rail transport, normally with interchange with other modes of public transport...

s, serve as the main public transport hub for the city, and have transfer available between rail services, and to rapid transit, tram or bus services.

Ownership

Traditionally, the infrastructure and rolling stock are owned and operated by the same company. This has often been by a national railway

National Railway

The National Railway or National Air Line Railroad was a planned railroad between New York City and Washington, D.C. in the United States around 1870...

, while other companies have had private railways. Since the 1980s, there has been an increasing tendency to split up railway companies, with separate companies owning the stock from those owning the infrastructure, particularly in Europe, where this is required by the European Union. This has allowed open access by any train operator to any portion of the European railway network.

In the U.S., virtually all rail networks and infrastructure are privately-owned with passenger lines, primarily Amtrak

Amtrak

The National Railroad Passenger Corporation, doing business as Amtrak , is a government-owned corporation that was organized on May 1, 1971, to provide intercity passenger train service in the United States. "Amtrak" is a portmanteau of the words "America" and "track". It is headquartered at Union...

, operating as tenants on the freight lines. Consequently, operations must be closely synchronized and coordinated between freight and passenger railways for timeliness of their schedules. Due to this shared system, both are regulated by the Federal Railroad Administration

Federal Railroad Administration

The Federal Railroad Administration is an agency in the United States Department of Transportation. The agency was created by the Department of Transportation Act of 1966...

(FRA) and follow the AREMA

American Railway Engineering and Maintenance-of-Way Association

The American Railway Engineering and Maintenance-of-Way Association is a North American railway industry group. It publishes recommended practices for the design, construction and maintenance of railway infrastructure, which are requirements in the United States and Canada.-Overview:AREMA is...

standards for track work and AAR

Association of American Railroads

The Association of American Railroads is an industry trade group representing primarily the major freight railroads of North America . Amtrak and some regional commuter railroads are also members...

standards for vehicles.

Financing

The main source of income for railway companies is from ticket

Train ticket

A train ticket is a ticket issued by a railway operator that enables the bearer to travel on the operator's network or a partner's network. Tickets can authorize the bearer to travel a set itinerary at a specific time , a set itinerary at any time , a set itinerary at multiple times, or an...

revenue (for passenger transport) and shipment fees for cargo. Discounts and monthly passes are sometimes available for frequent travellers. Freight revenue may be sold per container slot or for a whole train. Sometimes, the shipper owns the cars and only rents the haulage. For passenger transport, advertisement income can be significant.

Government may choose to give subsidies to rail operation, since rail transport has fewer externalities than other dominant modes of transport. If the railway company is state-owned, the state may simply provide direct subsidies in exchange for an increased production. If operations have been privatized, several options are available. Some countries have a system where the infrastructure is owned by a government agency or company—with open access to the tracks for any company that meets safety requirements. In such cases, the state may choose to provide the tracks free of charge, or for a fee that does not cover all costs. This is seen as analogous to the government providing free access to roads. For passenger operations, a direct subsidy may be paid to a public-owned operator, or public service obligation

Public Service Obligation

In transport, public service obligation or PSO is an arrangement in which a governing body or other authority offers an auction for subsidies, permit the winning company a monopoly to operate a specified service of public transport for a specified period of time for the given subsidy...

tender may be helt, and a time-limited contract awarded to the lowest bidder.

U.S.'s national passenger rail service, Amtrak

Amtrak

, is a private railroad company chartered by the government. Similarly, Canada's VIA Rail

VIA Rail

Via Rail Canada is an independent crown corporation offering intercity passenger rail services in Canada. It is headquartered near Montreal Central Station at 3 Place Ville-Marie in Montreal, Quebec....

system operates in the same fashion. As private passenger services lost significant ground in competition to the automobile and airplane and was forced out the market, they became stockholders of Amtrak either with a cash entrance fee or relinquishing their locomotives and rolling stock. Government aid supports Amtrak by supplying start-up capital

Capital (economics)

and makes up for loses at end of the fiscal year.

Safety

Rail transport is one of the safest forms of land travel. Trains can travel at very high speed, but they are heavy, are unable to deviate from the track and require a great distance to stop. Possible accidents include derailment

Derailment

A derailment is an accident on a railway or tramway in which a rail vehicle, or part or all of a train, leaves the tracks on which it is travelling, with consequent damage and in many cases injury and/or death....

(jumping the track), a collision with another train or collision with an automobile or other vehicle at level crossing

Level crossing

A level crossing occurs where a railway line is intersected by a road or path onone level, without recourse to a bridge or tunnel. It is a type of at-grade intersection. The term also applies when a light rail line with separate right-of-way or reserved track crosses a road in the same fashion...

s. The latter accounts for the majority of rail accidents and casualties. The most important safety measures to prevent accidents are strict operating rules, e.g. railway signalling

Railway signalling

Railway signalling is a system used to control railway traffic safely, essentially to prevent trains from colliding. Being guided by fixed rails, trains are uniquely susceptible to collision; furthermore, trains cannot stop quickly, and frequently operate at speeds that do not enable them to stop...

and gates or grade separation

Grade separation

Grade separation is the method of aligning a junction of two or more transport axes at different heights so that they will not disrupt the traffic flow on other transit routes when they cross each other. The composition of such transport axes does not have to be uniform; it can consist of a...

at crossings. Train whistle

Train whistle

A train whistle or air whistle, , is an audible signaling device on a steam locomotive used to warn that the train is approaching, and to communicate with rail workers....

s, bells or horns warn of the presence of a train, while trackside signals maintain the distances between trains.

An important element in the safety of many high-speed inter-city networks such as Japan's Shinkansen

Shinkansen

is the fact that trains only run on dedicated railway lines, without level crossings. This effectively eliminates the potential for collision with automobiles, other vehicles and pedestrians, vastly reduces the likelihood of collision with other trains and helps ensure services remain timely.

Maintenance

As in any infrastructure

Infrastructure

Infrastructure is basic physical and organizational structures needed for the operation of a society or enterprise, or the services and facilities necessary for an economy to function...

asset, railways must keep up with periodic inspection and maintenance in order to minimize effect of infrastructure failures that can disrupt freight revenue operations and passenger services. Because passengers are considered the most crucial cargo and usually operate at higher speeds, steeper grades, and higher capacity/frequency, their lines are especially important. Inspection practices include track geometry cars or walking inspection. Curve maintenance especially for transit services includes gauging, fastener tightening, and rail replacement. Rail corrugation is a common issue with transit systems due to the high number of light-axle, wheel passages which result in grinding of the wheel/rail interface. Since maintenance may overlap with operations, maintenance windows (nighttime hours, off-peak hours, altering train schedules or routes) must be closely followed. In addition, passenger safety during maintenance work (inter-track fencing, proper storage of materials, track work notices, hazards of equipment near states) must be regarded at all times. At times, maintenance access problems can emerge due to tunnels, elevated structures, and congested cityscapes. Here, specialized equipment, smaller versions of conventional maintenance gear are used.

Unlike highways or road networks where capacity is disaggregated into unlinked trips over individual route segments, railway capacity is fundamentally considered a network system. As a result, many components are causes and effects of system disruptions. Maintenance must acknowledge the vast array of a route's performance (type of train service, origination/destination, seasonal impacts), line's capacity (length, terrain, number of tracks, types of train control), train's throughput (max speeds, acceleration/deceleration rates), and service features with shared passenger-freight tracks (sidings, terminal capacities, switching routes, and design type).

Energy

Rail transport is an energy-efficient but capital-intensive, means of mechanized land transport. The tracks provide smooth and hard surfaces on which the wheels of the train can roll with a minimum of friction

Friction

Friction is the force resisting the relative motion of solid surfaces, fluid layers, and/or material elements sliding against each other. There are several types of friction:...

. Moving a vehicle on and/or through a medium (land, sea, or air) requires overcoming resistance

Friction

Friction is the force resisting the relative motion of solid surfaces, fluid layers, and/or material elements sliding against each other. There are several types of friction:...

to motion. A land vehicle's total resistance (in pounds

Pound (mass)

The pound or pound-mass is a unit of mass used in the Imperial, United States customary and other systems of measurement...

or Newtons) is a quadratic function

Quadratic function

A quadratic function, in mathematics, is a polynomial function of the formf=ax^2+bx+c,\quad a \ne 0.The graph of a quadratic function is a parabola whose axis of symmetry is parallel to the y-axis....

of the vehicle's speed:

where:

R denotes total resistance

a denotes initial constant resistance

v denotes speed

c denotes shape, frontal area, and sides of vehicle

v² denotes effect of air resistance

Essentially, resistance differs between vehicle's contact point and surface of roadway. Metal wheels on metal rails have a significant advantage of overcoming resistance compared to rubber-tired wheels on any road surface (railway - 0.001g at 10 mph and 0.024g at 60 mph; truck - 0.009g at 10 mph and 0.090 at 60 mph). In terms of cargo capacity combining speed and size being moved in a day (ton-miles/day):

human - can carry 100 lbs. 20 miles per day (one ton-mile/day)
horse and wheelbarrow - can carry 4 ton-miles/day
horse cart on good pavement - can carry 10 ton-miles/day
fully utility truck - can carry 20,000 ton-miles/day
long-haul train - can carry 500,000 ton-miles/day

In terms of motive power, the horsepower and weight ratio, used to overcome resistance to motion when locomotives convert fuel to heat for propulsion a slow-moving barge requires 0.2 hp/net ton, a railway and pipeline requires 2.5 hp/net ton, and truck requires 10 hp/net ton. However, at higher speeds, a railway overcomes the barge and proves most economical.

As an example, a typical modern wagon can hold up to 113 tonnes of freight on two four-wheel bogie

Bogie

A bogie is a wheeled wagon or trolley. In mechanics terms, a bogie is a chassis or framework carrying wheels, attached to a vehicle. It can be fixed in place, as on a cargo truck, mounted on a swivel, as on a railway carriage/car or locomotive, or sprung as in the suspension of a caterpillar...

s. The contact area between each wheel and the rail is a strip no more than a few millimetres wide, which minimizes friction. The track distributes the weight of the train evenly, allowing significantly greater loads per axle

Axle

An axle is a central shaft for a rotating wheel or gear. On wheeled vehicles, the axle may be fixed to the wheels, rotating with them, or fixed to its surroundings, with the wheels rotating around the axle. In the former case, bearings or bushings are provided at the mounting points where the axle...

and wheel than in road transport, leading to less wear and tear on the permanent way. This can save energy compared with other forms of transport, such as road transport, which depends on the friction between rubber tires and the road. Trains have a small frontal area in relation to the load they are carrying, which reduces air resistance and thus energy usage.

In addition, the presence of track guiding the wheels allows for very long trains to be pulled by one or a few engines and driven by a single operator, even around curves, which allows for economies of scale

Economies of scale

Economies of scale, in microeconomics, refers to the cost advantages that an enterprise obtains due to expansion. There are factors that cause a producer’s average cost per unit to fall as the scale of output is increased. "Economies of scale" is a long run concept and refers to reductions in unit...

in both manpower and energy use; by contrast, in road transport, more than two articulations

Articulated vehicle

An articulated vehicle is a vehicle which has a permanent or semi-permanent pivoting joint in its construction, allowing the vehicle to turn more sharply. There are many kinds of articulated vehicles, from heavy equipment to buses, trams and trains...

causes fishtailing

Fishtailing

Fishtailing is a vehicle handling problem which occurs when the rear wheels lose traction, resulting in oversteer. This can be caused by low friction surfaces...

and makes the vehicle unsafe.

Usage

Due to these benefits, rail transport is a major form of passenger and freight transport in many countries. In India, China, South Korea and Japan, many millions use trains as regular transport. It is widespread in European countries. Freight rail transport is widespread and heavily used in North America, but intercity passenger rail transport on that continent is relatively scarce outside the Northeast Corridor

Northeast Corridor

The Northeast Corridor is a fully electrified railway line owned primarily by Amtrak serving the Northeast megalopolis of the United States from Boston in the north, via New York to Washington, D.C. in the south, with branches serving other cities...

due to the loss of competition to other preferred modes, particular automobiles and airplanes.

Africa and South America have some extensive networks such as in South Africa, Northern Africa and Argentina; but some railways on these continents are isolated lines. Australia has a generally sparse network befitting its population density, but has some areas with significant networks, especially in the southeast. In addition to the previously existing east-west transcontinental line in Australia, a line from north to south has been constructed. The highest railway in the world is the line to Lhasa

Qingzang railway

The Qinghai–Xizang railway, Qingzang railway, or Qinghai–Tibet railway , is a high-elevation railway that connects Xining, Qinghai Province, to Lhasa, Tibet Autonomous Region, in People's Republic of China....

, in Tibet, partly running over permafrost territory. The western Europe region has the highest railway density in the world, and has many individual trains which operate through several countries despite technical and organizational differences in each national network.

Social/Economic Benefits

Railways have also been shown to contribute to social vibrancy and economic competitiveness in its ability to transport large amounts of customers and workers to city centers and inner suburbs

Inner suburbs

Inner suburb is a term used for a variety of suburban communities that are generally located very close to a large city. Their urban density is lower than the inner city or Central Business District ....

(i.e. Washington DC as a cultural/policy center due to metrorail

Metrorail

Metrorail may refer to:* Metrorail , a commuter rail system operator in South Africa** Metrorail Eastern Cape, commuter rail lines serving Port Elizabeth and East London...

system, San Francisco's lively downtown due to the BART system). Hong Kong

Hong Kong

Hong Kong is one of two Special Administrative Regions of the People's Republic of China , the other being Macau. A city-state situated on China's south coast and enclosed by the Pearl River Delta and South China Sea, it is renowned for its expansive skyline and deep natural harbour...

has recognized rail as "the backbone of the public transit system" and as such developed their franchised bus system and road infrastructure in compherensive alignment with their rail services. China's large cities including Beijing

Beijing

Beijing , also known as Peking , is the capital of the People's Republic of China and one of the most populous cities in the world, with a population of 19,612,368 as of 2010. The city is the country's political, cultural, and educational center, and home to the headquarters for most of China's...

, Shanghai

Shanghai

Shanghai is the largest city by population in China and the largest city proper in the world. It is one of the four province-level municipalities in the People's Republic of China, with a total population of over 23 million as of 2010...

, and Guangzhou

Guangzhou

Guangzhou , known historically as Canton or Kwangchow, is the capital and largest city of the Guangdong province in the People's Republic of China. Located in southern China on the Pearl River, about north-northwest of Hong Kong, Guangzhou is a key national transportation hub and trading port...

recognize rail transit lines as the framework and bus lines as the main body to their metropolitan transportation systems. The Japanese Shinkansen

Shinkansen

was built to meet the growing traffic demand in the "heart of Japan's industry and economy" situated on the Tokyo

Tokyo

, ; officially , is one of the 47 prefectures of Japan. Tokyo is the capital of Japan, the center of the Greater Tokyo Area, and the largest metropolitan area of Japan. It is the seat of the Japanese government and the Imperial Palace, and the home of the Japanese Imperial Family...

-Kobe

Kobe

, pronounced , is the fifth-largest city in Japan and is the capital city of Hyōgo Prefecture on the southern side of the main island of Honshū, approximately west of Osaka...

line.

As opposed to highway

Highway

expansion, indicative of the U.S. transportation policy, that incentivizes development of suburbs at the periphery, contributing to increased vehicle miles traveled, carbon emissions, development of greenfield

Greenfield

-Engineering:* Greenfield land, a piece of undeveloped land * One of several related terms:* Greenfield project, a project which lacks any constraints imposed by prior work...

spaces, and depletion of natural reserves, railways channel growth toward dense city agglomerations and along its artery. These sustainable arrangements revalue city spaces, local taxes, housing

House

A house is a building or structure that has the ability to be occupied for dwelling by human beings or other creatures. The term house includes many kinds of different dwellings ranging from rudimentary huts of nomadic tribes to free standing individual structures...

values, and promotion of mixed use development.