Dollis Brook Viaduct
Encyclopedia
The Dollis Brook Viaduct, also known as the Dollis Road Viaduct, Dollis Viaduct, Mill Hill Viaduct and Finchley Viaduct, is a railway viaduct
in Finchley
, North London
, United Kingdom
. It currently carries the London Underground
's Northern line
from Mill Hill East station
to Finchley Central station
. It is the highest point on the London Underground above ground level, reaching nearly 60 feet (18.3 m). It is located on a branch that was formerly part of the Edgware, Highgate and London Railway
.
which it crosses. The brook was marked on an 1877 Ordnance Survey
map and the name may have originated from a farm called Dollis, previously in Hendon
. This was earlier named Dalys in 1563, (the) Doles 1574, Dallys 1584 and in its current form of Dollis in 1822. This probably meant "the portions or shares of land (in the common field)", from the Middle English
word dole. The name is not thought to be connect with the area of Dollis Hill
, further south. Dollis Hill is thought to mean a "hill associated with a family called Dalley".
(GNR) from 1855-1861. The contractor that built the bridge was Smith, Knight & Co. The viaduct came into use on 22 August 1867 with the opening of the GNR's single-track Edgware, Highgate and London Railway
line from Finsbury Park
to Edgware
, via Finchley
and Mill Hill
, which was authorised by an Act of Parliament
in 1862.
Although built to carry two tracks, the viaduct initially carried only one. Following the construction of a branch northwards from Finchley to Barnet in 1872, the original Edgware route effectively became a branch of the newer line. In the 1920s, the London and North Eastern Railway
(LNER, successor to the GNR) planned to electrify the line but work was not carried out until the 1930s when the Northern Heights plan led to the doubling and electrification of the lines. This was in preparation for a transfer of the lines to the London Underground for it to form part of the system's Northern line
. The start of the Second World War prevented the plans being completed and only the section of the line to Mill Hill East was electrified and reopened in 1941, whilst the High Barnet branch was electrified in 1940. From this point on London Transport
trains used only one of the tracks on the Mill Hill branch and the other track was soon lifted. Freight on the line lasted until 1964 when the line west of Mill Hill East was abandoned, leaving the present arrangement.
es carry it across the valley of the Dollis Brook
, and over Dollis Road. Each arch spans 32 feet (9.8 m) at the springer level
, and is based on tapered piers
. In each pier there is an opening with an arched soffit
and a dished invert. The viaduct is made from brick. It is the highest point on both the Northern line and the highest point on the London Underground above ground level, reaching nearly 60 feet (18.3 m). It is not, however, the highest elevation
on the Underground system, which is near the Amersham station on the Metropolitan line
, at 150 metres (492.1 ft).
, a long distance footpath
between Moat Mount Open Space
in Mill Hill
and Hampstead Heath
. This is designed to link many green spaces and wildlife corridors along the way and is approximately 10 miles (16.1 km) long. The geology nearby is of London Clay
with small amounts of other rock types. An examination in the late 19th century of the railway cutting between Finchley and Hendon station
found a large extent of glacial beds
and fossil
s, and these were thought to extend as far north-west as the viaduct.
Viaduct
A viaduct is a bridge composed of several small spans. The term viaduct is derived from the Latin via for road and ducere to lead something. However, the Ancient Romans did not use that term per se; it is a modern derivation from an analogy with aqueduct. Like the Roman aqueducts, many early...
in Finchley
Finchley
Finchley is a district in Barnet in north London, England. Finchley is on high ground, about north of Charing Cross. It formed an ancient parish in the county of Middlesex, becoming a municipal borough in 1933, and has formed part of Greater London since 1965...
, North London
North London
North London is the northern part of London, England. It is an imprecise description and the area it covers is defined differently for a range of purposes. Common to these definitions is that it includes districts located north of the River Thames and is used in comparison with South...
, 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...
. It currently carries the London Underground
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...
's Northern line
Northern Line
The Northern line is a London Underground line. It is coloured black on the Tube map.For most of its length it is a deep-level tube line. The line carries 206,734,000 passengers per year. This is the highest number of any line on the London Underground system, but the Northern line is unique in...
from Mill Hill East station
Mill Hill East tube station
Mill Hill East tube station is a London Underground station in Mill Hill in North London.The station is on the High Barnet branch of the Northern Line, and is the terminus, and only station, of a branch from Finchley Central station...
to Finchley Central station
Finchley Central tube station
Finchley Central tube station is a London Underground station in the Church End area of Finchley, North London.The station is on the High Barnet branch of the Northern line, between West Finchley and East Finchley stations and is the junction for the short branch to Mill Hill East station...
. It is the highest point on the London Underground above ground level, reaching nearly 60 feet (18.3 m). It is located on a branch that was formerly part of the Edgware, Highgate and London Railway
Edgware, Highgate and London Railway
The Edgware, Highgate and London Railway was a railway in north London. The railway was a precursor of parts of London Underground's Northern Line and was, in the 1930s the core of an ambitious expansion plan for that line which was thwarted by the Second World War...
.
Etymology
The official name of the viaduct is taken from Dollis BrookDollis Brook
Dollis Brook runs through the London Borough of Barnet in North London. It is a tributary of the River Brent, which is itself a tributary of the River Thames. The Dollis Valley Greenwalk follows almost all of Dollis Brook, apart from a short section at the beginning which passes through private...
which it crosses. The brook was marked on an 1877 Ordnance Survey
Ordnance Survey
Ordnance Survey , an executive agency and non-ministerial government department of the Government of the United Kingdom, is the national mapping agency for Great Britain, producing maps of Great Britain , and one of the world's largest producers of maps.The name reflects its creation together with...
map and the name may have originated from a farm called Dollis, previously in Hendon
Hendon
Hendon is a London suburb situated northwest of Charing Cross.-History:Hendon was historically a civil parish in the county of Middlesex. The manor is described in Domesday , but the name, 'Hendun' meaning 'at the highest hill', is earlier...
. This was earlier named Dalys in 1563, (the) Doles 1574, Dallys 1584 and in its current form of Dollis in 1822. This probably meant "the portions or shares of land (in the common field)", from the Middle English
Middle English
Middle English is the stage in the history of the English language during the High and Late Middle Ages, or roughly during the four centuries between the late 11th and the late 15th century....
word dole. The name is not thought to be connect with the area of Dollis Hill
Dollis Hill
Dollis Hill is an area of north-west London. It lies close to Willesden, in the London Borough of Brent. As a result, Dollis Hill is sometimes referred as being part of Willesden, especially by the national press...
, further south. Dollis Hill is thought to mean a "hill associated with a family called Dalley".
History
The viaduct was designed by John Fowler and Walter Brydone, chief engineer for the Great Northern RailwayGreat Northern Railway (Great Britain)
The Great Northern Railway was a British railway company established by the Great Northern Railway Act of 1846. On 1 January 1923 the company lost its identity as a constituent of the newly formed London and North Eastern Railway....
(GNR) from 1855-1861. The contractor that built the bridge was Smith, Knight & Co. The viaduct came into use on 22 August 1867 with the opening of the GNR's single-track Edgware, Highgate and London Railway
Edgware, Highgate and London Railway
The Edgware, Highgate and London Railway was a railway in north London. The railway was a precursor of parts of London Underground's Northern Line and was, in the 1930s the core of an ambitious expansion plan for that line which was thwarted by the Second World War...
line from Finsbury Park
Finsbury Park station
Finsbury Park Station is a busy transport interchange in North London. The interchange consists of an interconnected National Rail station, London Underground station and two bus stations. The main entrances are by the eastern bus station on Station Place...
to Edgware
Edgware railway station
Edgware railway station was a London and North Eastern Railway station in Station Road, Edgware, Greater London. It is not to be confused with the London Underground Northern line Edgware station approximately 200 metres to the north east.-History:...
, via Finchley
Finchley
Finchley is a district in Barnet in north London, England. Finchley is on high ground, about north of Charing Cross. It formed an ancient parish in the county of Middlesex, becoming a municipal borough in 1933, and has formed part of Greater London since 1965...
and Mill Hill
Mill Hill
Mill Hill is a place in the London Borough of Barnet. It is a suburb situated 9 miles north west of Charing Cross. Mill Hill was in the historic county of Middlesex until it was absorbed by London...
, which was authorised by an Act of Parliament
Act of Parliament
An Act of Parliament is a statute enacted as primary legislation by a national or sub-national parliament. In the Republic of Ireland the term Act of the Oireachtas is used, and in the United States the term Act of Congress is used.In Commonwealth countries, the term is used both in a narrow...
in 1862.
London and North Eastern Railway
The London and North Eastern Railway was the second-largest of the "Big Four" railway companies created by the Railways Act 1921 in Britain...
(LNER, successor to the GNR) planned to electrify the line but work was not carried out until the 1930s when the Northern Heights plan led to the doubling and electrification of the lines. This was in preparation for a transfer of the lines to the London Underground for it to form part of the system's Northern line
Northern Line
The Northern line is a London Underground line. It is coloured black on the Tube map.For most of its length it is a deep-level tube line. The line carries 206,734,000 passengers per year. This is the highest number of any line on the London Underground system, but the Northern line is unique in...
. The start of the Second World War prevented the plans being completed and only the section of the line to Mill Hill East was electrified and reopened in 1941, whilst the High Barnet branch was electrified in 1940. From this point on London Transport
London Transport Executive
The London Transport Executive was the organisation responsible for public transport in the Greater London area, UK, between 1948-1962. In common with all London transport authorities from 1933 to 2000, the public name and operational brand of the organisation was London Transport.-Creation:On 1...
trains used only one of the tracks on the Mill Hill branch and the other track was soon lifted. Freight on the line lasted until 1964 when the line west of Mill Hill East was abandoned, leaving the present arrangement.
Length, span and architecture
The viaduct's 13 segmental archArch
An arch is a structure that spans a space and supports a load. Arches appeared as early as the 2nd millennium BC in Mesopotamian brick architecture and their systematic use started with the Ancient Romans who were the first to apply the technique to a wide range of structures.-Technical aspects:The...
es carry it across the valley of the Dollis Brook
Dollis Brook
Dollis Brook runs through the London Borough of Barnet in North London. It is a tributary of the River Brent, which is itself a tributary of the River Thames. The Dollis Valley Greenwalk follows almost all of Dollis Brook, apart from a short section at the beginning which passes through private...
, and over Dollis Road. Each arch spans 32 feet (9.8 m) at the springer level
Springer (architecture)
A springer is an architectural term for the lowest voussoir on each side of an arch. Since it is the bottom-most element of the arch, it is where the arch support terminates at the responds. It rests on the impost or pier of the arch, that is, the topmost part of the abutment, from which the arch...
, and is based on tapered piers
Pier (architecture)
In architecture, a pier is an upright support for a superstructure, such as an arch or bridge. Sections of wall between openings function as piers. The simplest cross section of the pier is square, or rectangular, although other shapes are also common, such as the richly articulated piers of Donato...
. In each pier there is an opening with an arched soffit
Soffit
Soffit , in architecture, describes the underside of any construction element...
and a dished invert. The viaduct is made from brick. It is the highest point on both the Northern line and the highest point on the London Underground above ground level, reaching nearly 60 feet (18.3 m). It is not, however, the highest elevation
Elevation
The elevation of a geographic location is its height above a fixed reference point, most commonly a reference geoid, a mathematical model of the Earth's sea level as an equipotential gravitational surface ....
on the Underground system, which is near the Amersham station on the Metropolitan line
Metropolitan Line
The Metropolitan line is part of the London Underground. It is coloured in Transport for London's Corporate Magenta on the Tube map and in other branding. It was the first underground railway in the world, opening as the Metropolitan Railway on 10 January 1863...
, at 150 metres (492.1 ft).
Around the viaduct
Below the viaduct can be found the Dollis Valley GreenwalkDollis Valley Greenwalk
The Dollis Valley Greenwalk is a long distance footpath in the London Borough of Barnet between Moat Mount Nature Reserve in Mill Hill and Hampstead Heath. The route is designed to act as a link between the Capital Ring and the London Loop,and between the many green spaces and wildlife corridors...
, a long distance footpath
Long-distance footpaths in the United Kingdom
-England and Wales: National Trails:National Trails are distinguished by being maintained by the National Trails organization . , there are fifteen such trails, one of which is not yet complete....
between Moat Mount Open Space
Barnet parks and open spaces
The London Borough of Barnet, located on the northern periphery of London and having much of the area within its boundaries in the Metropolitan Green Belt, has a large number of parks and open spaces...
in Mill Hill
Mill Hill
Mill Hill is a place in the London Borough of Barnet. It is a suburb situated 9 miles north west of Charing Cross. Mill Hill was in the historic county of Middlesex until it was absorbed by London...
and Hampstead Heath
Hampstead Heath
Hampstead Heath is a large, ancient London park, covering . This grassy public space sits astride a sandy ridge, one of the highest points in London, running from Hampstead to Highgate, which rests on a band of London clay...
. This is designed to link many green spaces and wildlife corridors along the way and is approximately 10 miles (16.1 km) long. The geology nearby is of London Clay
London Clay
The London Clay Formation is a marine geological formation of Ypresian age which crops out in the southeast of England. The London Clay is well known for the fossils it contains. The fossils from the Lower Eocene indicate a moderately warm climate, the flora being tropical or subtropical...
with small amounts of other rock types. An examination in the late 19th century of the railway cutting between Finchley and Hendon station
Finchley Central tube station
Finchley Central tube station is a London Underground station in the Church End area of Finchley, North London.The station is on the High Barnet branch of the Northern line, between West Finchley and East Finchley stations and is the junction for the short branch to Mill Hill East station...
found a large extent of glacial beds
Till
thumb|right|Closeup of glacial till. Note that the larger grains in the till are completely surrounded by the matrix of finer material , and this characteristic, known as matrix support, is diagnostic of till....
and fossil
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...
s, and these were thought to extend as far north-west as the viaduct.