Northern Line
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| Circle | |
| District | |
| East London | |
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| Jubilee | |
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| Northern | |
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| Docklands Light Railway | |
The Northern Line is a deep-level tube line of the London Underground, coloured black on the Tube map. With two routes through the central area and two to the north, it is one of the more complicated lines on the system.
A typical Northern Line platform, at Bank underground station Inside a Northern Line carriage
City & South London Railway train, 1890
In 1913 the two lines came into common ownership, and during the 1920s connections were built so that the two lines joined at Camden Town and Kennington. The tunnels of the CSLR were also expanded to match the standard size and the lines were extended to Morden in the south and Edgware in the north. The resulting line became known as the Morden-Edgware Line, and was eventually named the Northern Line in 1937.
After Nationalisation in 1933 the Northern City Line, which ran from Moorgate to Finsbury Park, was part of the Underground; it was operated as part of the Northern Line, though it was never connected to it.
After the War, the area beyond Edgware was made part of the Green Belt, and the potential demand for services from Bushey Heath thus vanished. Available funds were directed towards completing the eastern extension of the Central Line instead, and the Northern Heights plan was dropped. The line from Finsbury Park to Muswell Hill and Alexandra Palace via the surface platforms at Highgate was closed to passenger traffic in 1954. A local pressure group, the Muswell Hill Metro Group, campaigns to reopen this route as a light rail service. So far there is no sign of movement on this issue; the route, now the "Parkland Walk", is highly valued by walkers and cyclists and suggestions in the 90s that it could in part become a road were met with fierce opposition.
The suburban railway heritage of the High Barnet branch beyond Highgate can be seen in the design of the stations.
In the 1980s and 1990s the line was nicknamed the "Misery Line", though its reputation improved somewhat after the introduction of new rolling stock in the late 1990s.
In 2003, a train derailed at Camden Town tube station. This damaged points and signals, and trains did not cross there while repairs were underway - trains coming from Edgware only worked the Bank branch and trains from High Barnet and Mill Hill East only served the Charing Cross branch. This situation was resolved when the crossing reopened, after much repair work and safety analysis and testing, on 7th March 2004.
A joint report by London Underground and its maintenance contractor Tubelines concluded that poor track geometry was the main cause, and that, because of the geometry, extra friction arising out of striations (scratches) on a newly installed set of points had allowed the leading wheel of the last carriage to climb the rail and so derail. The track geometry at the derailment site is a very tight bend and tight tunnel bore, which precludes the normal solution for this sort of geometry of canting the track by dipping the height of one rail relative to the other.Stations
High Barnet branch
Edgware branch
Camden Town
The junctions connecting the two northern branches of the Northern Line to the two central branches are just south of Camden Town station. The station has a pair of platforms on each of the two northern branches, and southbound trains can depart toward either Charing Cross or Bank from either of the two southbound platforms.Charing Cross branch
(Also known as the West End branch.)
Southbound trains on this branch often terminate at Kennington, where they reverse by means of a loop track.Bank branch
(Also known as the City Branch.)Morden branch
History
Formation of the Northern Line
New Works Programme 1935-40: the Northern Heights plan
In June 1935 an ambitious plan of new extensions was announced by LT, including a complex of lines north of Highgate across the "Northern Heights," linking the Highgate branch and the Northern City Line to an existing suburban branch line which ran on the surface from Finsbury Park to Edgware via Highgate, with branches to Alexandra Palace and High Barnet. The line taken over would also be extended beyond Edgware to Bushey Heath and a new depot at Aldenham. This would involve electrification of the surface lines (served by steam trains at the time) and the construction of two new stretches of track: a connection between the Northern City and Finsbury Park station on the surface, and an extension of the Highgate branch tube to the LNER line near East Finchley via new deep-level platforms below the existing Highgate station.
More recent developments
In 1975 the Northern City Line, known by that time as the Highbury branch, became part of British Rail. It is now served by WAGN.