The meridian 100° west of Greenwich

Prime Meridian

The Prime Meridian is the meridian at which the longitude is defined to be 0°.The Prime Meridian and its opposite the 180th meridian , which the International Date Line generally follows, form a great circle that divides the Earth into the Eastern and Western Hemispheres.An international...

is a line of longitude

Longitude

Longitude is a geographic coordinate that specifies the east-west position of a point on the Earth's surface. It is an angular measurement, usually expressed in degrees, minutes and seconds, and denoted by the Greek letter lambda ....

 that extends from the North Pole

North Pole

The North Pole, also known as the Geographic North Pole or Terrestrial North Pole, is, subject to the caveats explained below, defined as the point in the northern hemisphere where the Earth's axis of rotation meets its surface...

 across the Arctic Ocean

Arctic Ocean

The Arctic Ocean, located in the Northern Hemisphere and mostly in the Arctic north polar region, is the smallest and shallowest of the world's five major oceanic divisions...

, North America

North America

North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

, the Pacific Ocean

Pacific Ocean

The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...

, the Southern Ocean

Southern Ocean

The Southern Ocean comprises the southernmost waters of the World Ocean, generally taken to be south of 60°S latitude and encircling Antarctica. It is usually regarded as the fourth-largest of the five principal oceanic divisions...

, and Antarctica to the South Pole

South Pole

The South Pole, also known as the Geographic South Pole or Terrestrial South Pole, is one of the two points where the Earth's axis of rotation intersects its surface. It is the southernmost point on the surface of the Earth and lies on the opposite side of the Earth from the North Pole...

.

The 100th meridian west forms a great circle

Great circle

A great circle, also known as a Riemannian circle, of a sphere is the intersection of the sphere and a plane which passes through the center point of the sphere, as opposed to a general circle of a sphere where the plane is not required to pass through the center...

 with the 80th meridian east

80th meridian east

The meridian 80° east of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, Asia, the Indian Ocean, the Southern Ocean, and Antarctica to the South Pole....

.

Geography

Starting at the North Pole

North Pole

The North Pole, also known as the Geographic North Pole or Terrestrial North Pole, is, subject to the caveats explained below, defined as the point in the northern hemisphere where the Earth's axis of rotation meets its surface...

 and heading south to the South Pole

South Pole

The South Pole, also known as the Geographic South Pole or Terrestrial South Pole, is one of the two points where the Earth's axis of rotation intersects its surface. It is the southernmost point on the surface of the Earth and lies on the opposite side of the Earth from the North Pole...

, the 100th meridian west passes through:

Co-ordinates	Country, territory or sea	Notes
90°0′N 100°0′W	Arctic Ocean Arctic Ocean The Arctic Ocean, located in the Northern Hemisphere and mostly in the Arctic north polar region, is the smallest and shallowest of the world's five major oceanic divisions...
80°6′N 100°0′W		Nunavut Nunavut Nunavut is the largest and newest federal territory of Canada; it was separated officially from the Northwest Territories on April 1, 1999, via the Nunavut Act and the Nunavut Land Claims Agreement Act, though the actual boundaries had been established in 1993...  - Meighen Island Meighen Island Meighen Island is an uninhabited member of the Queen Elizabeth Islands, part of the Canadian Arctic Archipelago, in the Qikiqtaaluk Region of Nunavut, Canada. Located at 79°55'N 99°30'W, it measures in size and is topped with an ice cap. The island is continuously icebound, and its northwestern...
79°52′N 100°0′W	Peary Channel Peary Channel The Peary Channel is a waterway in the territory of Nunavut. It is an arm of the Arctic Ocean, and it spreads southeast between Meighen Island to the north, Axel Heiberg Island to the east, Amund Ringnes Island to the southeast, Ellef Ringnes Island to the south. The channel is approximately long...
78°44′N 100°0′W		Nunavut Nunavut Nunavut is the largest and newest federal territory of Canada; it was separated officially from the Northwest Territories on April 1, 1999, via the Nunavut Act and the Nunavut Land Claims Agreement Act, though the actual boundaries had been established in 1993...  - Ellef Ringnes Island Ellef Ringnes Island Ellef Ringnes Island is one of the Sverdrup Islands in Qikiqtaaluk Region, Nunavut, Canada. Also a member of the Queen Elizabeth Islands and Canadian Arctic Archipelago, it is located in the Arctic Ocean, east of Borden Island, and west of Amund Ringnes Island...
77°48′N 100°0′W	Unnamed waterbody
76°45′N 100°0′W		Nunavut Nunavut Nunavut is the largest and newest federal territory of Canada; it was separated officially from the Northwest Territories on April 1, 1999, via the Nunavut Act and the Nunavut Land Claims Agreement Act, though the actual boundaries had been established in 1993...  - Berkeley Islands Berkeley Islands The Berkeley Islands are an uninhabited island group in the Qikiqtaaluk Region of northern Canada's territory of Nunavut....  and Bathurst Island Bathurst Island A member of the Canadian Arctic Archipelago, Bathurst Island is one of the Queen Elizabeth Islands in Nunavut Territory, Canada. The area of the island is estimated at , making it the 54th largest island in the world and Canada's 13th largest island. It is uninhabited.The island is low-lying with...
74°59′N 100°0′W	Parry Channel Parry Channel The Parry Channel is a natural waterway through thecentral Canadian Arctic Archipelago in the territory of Nunavut. It runs east to west, connecting Baffin Bay in the east with the Beaufort Sea in the west. The channel separates the Queen Elizabeth Islands to the north from the rest of...
73°57′N 100°0′W		Nunavut Nunavut Nunavut is the largest and newest federal territory of Canada; it was separated officially from the Northwest Territories on April 1, 1999, via the Nunavut Act and the Nunavut Land Claims Agreement Act, though the actual boundaries had been established in 1993...  - Prince of Wales Island
71°52′N 100°0′W	M'Clintock Channel M'Clintock Channel M'Clintock Channel is located in the territory of Nunavut, Canada. The channel, an arm of the Arctic Ocean, divides Victoria Island from Prince of Wales Island. This channel is named after Sir Francis Leopold McClintock, in Irish explorer in the British Royal Navy, famous for his Canadian Arctic...
70°35′N 100°0′W	Larsen Sound Larsen Sound Larsen Sound is an Arctic waterway in the Kitikmeot Region, Nunavut, Canada.It is located south of Prince of Wales Island, west of the Boothia Peninsula, north of King William Island and east of Gateshead Island...	Passing just east of Gateshead Island Gateshead Island Gateshead Island is an island located in the Kitikmeot Region of Nunavut, Canada. Located in M'Clintock Channel, the area of Gateshead Island is around . It is an important polar bear denning area.... , Nunavut Nunavut Nunavut is the largest and newest federal territory of Canada; it was separated officially from the Northwest Territories on April 1, 1999, via the Nunavut Act and the Nunavut Land Claims Agreement Act, though the actual boundaries had been established in 1993... ,
69°58′N 100°0′W	Victoria Strait Victoria Strait Victoria Strait is a strait in northern Canada that lies in Nunavut off the mainland in the Arctic Ocean. It is between Victoria Island to the west and King William Island to the east. From the north the strait links the M'Clintock Channel and the Larsen Sound with the Queen Maud Gulf to the south...
69°3′N 100°0′W		Nunavut Nunavut Nunavut is the largest and newest federal territory of Canada; it was separated officially from the Northwest Territories on April 1, 1999, via the Nunavut Act and the Nunavut Land Claims Agreement Act, though the actual boundaries had been established in 1993...  - Royal Geographical Society Island Royal Geographical Society Island Royal Geographical Society Island is an island in Victoria Strait, within the Queen Maud Gulf, in the north Canadian territory of Nunavut.It has an area of .... s
68°57′N 100°0′W	Queen Maud Gulf Queen Maud Gulf Queen Maud Gulf lies between the northern coast of the mainland and the southeastern corner of Victoria Island in Nunavut, Canada. At its western end lies Cambridge Bay, leading to Dease Strait; to the east lies Simpson Strait; and to the north, Victoria Strait.It was named by the Norwegian...	Passing just east of Hat Island Hat Island (Victoria Strait) Hat Island is a small uninhabited island located in the Kitikmeot Region of Nunavut, Canada. The island is situated in Victoria Strait approximately southeast of Victoria Island and southwest of King William Island.... , Nunavut Nunavut Nunavut is the largest and newest federal territory of Canada; it was separated officially from the Northwest Territories on April 1, 1999, via the Nunavut Act and the Nunavut Land Claims Agreement Act, though the actual boundaries had been established in 1993... ,
67°50′N 100°0′W		Nunavut Nunavut Nunavut is the largest and newest federal territory of Canada; it was separated officially from the Northwest Territories on April 1, 1999, via the Nunavut Act and the Nunavut Land Claims Agreement Act, though the actual boundaries had been established in 1993... > Manitoba Manitoba Manitoba is a Canadian prairie province with an area of . The province has over 110,000 lakes and has a largely continental climate because of its flat topography. Agriculture, mostly concentrated in the fertile southern and western parts of the province, is vital to the province's economy; other...
49°0′N 100°0′W		North Dakota North Dakota North Dakota is a state located in the Midwestern region of the United States of America, along the Canadian border. The state is bordered by Canada to the north, Minnesota to the east, South Dakota to the south and Montana to the west. North Dakota is the 19th-largest state by area in the U.S.... > South Dakota South Dakota South Dakota is a state located in the Midwestern region of the United States. It is named after the Lakota and Dakota Sioux American Indian tribes. Once a part of Dakota Territory, South Dakota became a state on November 2, 1889. The state has an area of and an estimated population of just over...  - 45°56′N 100°0′W > Nebraska Nebraska Nebraska is a state on the Great Plains of the Midwestern United States. The state's capital is Lincoln and its largest city is Omaha, on the Missouri River....  - 43°0′N 100°0′W > Kansas Kansas Kansas is a US state located in the Midwestern United States. It is named after the Kansas River which flows through it, which in turn was named after the Kansa Native American tribe, which inhabited the area. The tribe's name is often said to mean "people of the wind" or "people of the south...  - 40°0′N 100°0′W > Oklahoma Oklahoma Oklahoma is a state located in the South Central region of the United States of America. With an estimated 3,751,351 residents as of the 2010 census and a land area of 68,667 square miles , Oklahoma is the 28th most populous and 20th-largest state...  - 37°0′N 100°0′W > Texas Texas Texas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in...  / Oklahoma Oklahoma Oklahoma is a state located in the South Central region of the United States of America. With an estimated 3,751,351 residents as of the 2010 census and a land area of 68,667 square miles , Oklahoma is the 28th most populous and 20th-largest state...  border - 36°30′N 100°0′W > Texas Texas Texas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in...  - 34°34′N 100°0′W
28°0′N 100°0′W		Coahuila Coahuila Coahuila, formally Coahuila de Zaragoza , officially Estado Libre y Soberano de Coahuila de Zaragoza is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico... > Nuevo León Nuevo León Nuevo León It is located in Northeastern Mexico. It is bordered by the states of Tamaulipas to the north and east, San Luis Potosí to the south, and Coahuila to the west. To the north, Nuevo León has a 15 kilometer stretch of the U.S.-Mexico border adjacent to the U.S... > Tamaulipas Tamaulipas Tamaulipas officially Estado Libre y Soberano de Tamaulipas is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided in 43 municipalities and its capital city is Ciudad Victoria. The capital city was named after Guadalupe Victoria, the... > San Luis Potosí San Luis Potosí San Luis Potosí officially Estado Libre y Soberano de San Luis Potosí is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided in 58 municipalities and its capital city is San Luis Potosí.... > Tamaulipas Tamaulipas Tamaulipas officially Estado Libre y Soberano de Tamaulipas is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided in 43 municipalities and its capital city is Ciudad Victoria. The capital city was named after Guadalupe Victoria, the... > San Luis Potosí San Luis Potosí San Luis Potosí officially Estado Libre y Soberano de San Luis Potosí is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided in 58 municipalities and its capital city is San Luis Potosí.... > Guanajuato Guanajuato Guanajuato officially Estado Libre y Soberano de Guanajuato is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided in 46 municipalities and its capital city is Guanajuato.... > Querétaro Querétaro Querétaro officially Estado Libre y Soberano de Querétaro de Arteaga is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided into 18 municipalities and its capital city is Santiago de Querétaro.... > Mexico State > Guerrero Guerrero Guerrero officially Estado Libre y Soberano de Guerrero is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided in 81 municipalities and its capital city is Chilpancingo....
16°54′N 100°0′W	Pacific Ocean Pacific Ocean The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...
60°0′S 100°0′W	Southern Ocean Southern Ocean The Southern Ocean comprises the southernmost waters of the World Ocean, generally taken to be south of 60°S latitude and encircling Antarctica. It is usually regarded as the fourth-largest of the five principal oceanic divisions...
71°55′S 100°0′W	Antarctica	Unclaimed territory

United States

In the United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 the meridian 100° west of Greenwich forms the eastern border of the Texas panhandle

Texas Panhandle

The Texas Panhandle is a region of the U.S. state of Texas consisting of the northernmost 26 counties in the state. The panhandle is a rectangular area bordered by New Mexico to the west and Oklahoma to the north and east...

 with Oklahoma

Oklahoma

Oklahoma is a state located in the South Central region of the United States of America. With an estimated 3,751,351 residents as of the 2010 census and a land area of 68,667 square miles , Oklahoma is the 28th most populous and 20th-largest state...

 (which traces its origin to the Adams-Onís Treaty

Adams-Onís Treaty

The Adams–Onís Treaty of 1819, also known as the Transcontinental Treaty or the Purchase of Florida, was a treaty between the United States and Spain in 1819 that gave Florida to the U.S. and set out a boundary between the U.S. and New Spain . It settled a standing border dispute between the two...

 in 1819 which settled the border between New Spain

New Spain

New Spain, formally called the Viceroyalty of New Spain , was a viceroyalty of the Spanish colonial empire, comprising primarily territories in what was known then as 'América Septentrional' or North America. Its capital was Mexico City, formerly Tenochtitlan, capital of the Aztec Empire...

 and the United States between the Red River

Red River (Mississippi watershed)

The Red River, or sometimes the Red River of the South, is a major tributary of the Mississippi and Atchafalaya Rivers in the southern United States of America. The river gains its name from the red-bed country of its watershed. It is one of several rivers with that name...

 and Arkansas River

Arkansas River

The Arkansas River is a major tributary of the Mississippi River. The Arkansas generally flows to the east and southeast as it traverses the U.S. states of Colorado, Kansas, Oklahoma, and Arkansas. The river's initial basin starts in the Western United States in Colorado, specifically the Arkansas...

). Dodge City, Kansas

Dodge City, Kansas

Dodge City is a city in, and the county seat of, Ford County, Kansas, United States. Named after nearby Fort Dodge, the city is famous in American culture for its history as a wild frontier town of the Old West. As of the 2010 census, the city population was 27,340.-History:The first settlement of...

 lies exactly at the intersection of the Arkansas River and the 100th meridian.

In the central Great Plains

Great Plains

The Great Plains are a broad expanse of flat land, much of it covered in prairie, steppe and grassland, which lies west of the Mississippi River and east of the Rocky Mountains in the United States and Canada. This area covers parts of the U.S...

, the meridian roughly marks the western boundary of the normal reach of moist air from the Gulf of Mexico

Gulf of Mexico

The Gulf of Mexico is a partially landlocked ocean basin largely surrounded by the North American continent and the island of Cuba. It is bounded on the northeast, north and northwest by the Gulf Coast of the United States, on the southwest and south by Mexico, and on the southeast by Cuba. In...

, and the approximate boundary (although some areas do push the boundary slightly farther east) between the semi-arid climate to the west and the humid continental

Humid continental climate

A humid continental climate is a climatic region typified by large seasonal temperature differences, with warm to hot summers and cold winters....

 (north of about 37°N

37th parallel north

The 37th parallel north is a circle of latitude that is 37 degrees north of the Earth's equatorial plane. It crosses Europe, the Mediterranean Sea, Africa, Asia, the Pacific Ocean, North America, and the Atlantic Ocean....

) and humid subtropical

Humid subtropical climate

A humid subtropical climate is a climate zone characterized by hot, humid summers and mild to cool winters...

 (south of about 37°N

37th parallel north

The 37th parallel north is a circle of latitude that is 37 degrees north of the Earth's equatorial plane. It crosses Europe, the Mediterranean Sea, Africa, Asia, the Pacific Ocean, North America, and the Atlantic Ocean....

) climates to the east. The type of agriculture

Agriculture

Agriculture is the cultivation of animals, plants, fungi and other life forms for food, fiber, and other products used to sustain life. Agriculture was the key implement in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that nurtured the...

 west of the meridian typically relies heavily on irrigation

Irrigation

Irrigation may be defined as the science of artificial application of water to the land or soil. It is used to assist in the growing of agricultural crops, maintenance of landscapes, and revegetation of disturbed soils in dry areas and during periods of inadequate rainfall...

. Historically the meridian has often been taken as a rough boundary between the eastern and western United States. White settlement, spreading westward after 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...

, encroached in the meridian in the 1870s.

A sign across U.S. Highway 30 in Cozad

Cozad, Nebraska

Cozad is a city in Dawson County, Nebraska, United States. The population was 3,977 at the 2010 census. The town is on the Great Plains of central Nebraska, along the Union Pacific Railroad and U.S. Highway 30, just north of the Platte River...

, Nebraska

Nebraska

Nebraska is a state on the Great Plains of the Midwestern United States. The state's capital is Lincoln and its largest city is Omaha, on the Missouri River....

 prominently marks the place where the meridian intersects the routes of the Oregon Trail

Oregon Trail

The Oregon Trail is a historic east-west wagon route that connected the Missouri River to valleys in Oregon and locations in between.After 1840 steam-powered riverboats and steamboats traversing up and down the Ohio, Mississippi and Missouri rivers sped settlement and development in the flat...

, Pony Express

Pony Express

The Pony Express was a fast mail service crossing the Great Plains, the Rocky Mountains, and the High Sierra from St. Joseph, Missouri, to Sacramento, California, from April 3, 1860 to October 1861...

, transcontinental railroad, and the Lincoln Highway

Lincoln Highway

The Lincoln Highway was the first road across the United States of America.Conceived and promoted by entrepreneur Carl G. Fisher, the Lincoln Highway spanned coast-to-coast from Times Square in New York City to Lincoln Park in San Francisco, originally through 13 states: New York, New Jersey,...

.

In popular culture

Wallace Stegner

Wallace Stegner

Wallace Earle Stegner was an American historian, novelist, short story writer, and environmentalist, often called "The Dean of Western Writers"...

's Beyond the Hundredth Meridian (1954), is a biography of John Wesley Powell

John Wesley Powell

John Wesley Powell was a U.S. soldier, geologist, explorer of the American West, and director of major scientific and cultural institutions...

, an explorer of the American West.
The song "At the Hundredth Meridian

At the Hundredth Meridian

"At the Hundredth Meridian" is the fourth single by The Tragically Hip from the band's 1992 album, Fully Completely. The song is a reference to the 100th meridian west, which is a line of longitude that separates much of Western Canada from the Central and Atlantic regions of Canada and is where...

" by The Tragically Hip

The Tragically Hip

The Tragically Hip, often referred to simply as The Hip, is a Canadian rock band from Kingston, Ontario, consisting of Gordon Downie , Paul Langlois , Rob Baker , Gord Sinclair and Johnny Fay . Since their formation in 1983 they have released 12 studio albums, two live albums, and 46 singles...

is about the 100th meridian west, specifically in Canada, and how it has traditionally been considered "where the great plains begin."

External links

• Canadian Maps of the 100th Meridian