London Underground

The London Underground (often shortened to the Underground and nicknamed the Tube) is part of the suburban railway network in London, UK. The Underground serves 270 stations and operates 402km of track, making it the largest part of London's suburban railway network, and the third-largest underground metro system in the world. 
With the first line opening in 1863, it isalso the oldest underground railway system in the world.
==History==
The original lines (Cut and cover lines, Earlier Tube lines) were built by various competing companies which opted to earn profits during the Industrial Revolution Era.
The Underground serves 270 stations and has 402 kilometres (250 mi) of track, 45 per cent of which is underground. It also has the largest number of stations. The tube is an international icon for London, with the tube map, considered a design classic, having influenced many other transport maps worldwide. Although also shown on the Tube map, the Docklands Light Railway (DLR), London Overground, and the Emirates Air Line are not part of the London Underground network but are part of the London Metro (fixed rail transport in London). The tube map could also be considered to be the 'Metro Map'.
The underground pays for itself 86%.
==Lines==
===Bakerloo Line===
The Bakerloo Line is a line on the Tube network that operates from the north to the south in a simmilar pattern to the Northern Line.
As of 2009, it has the second oldest stock on the Network after the picciadilly line, and is famous for historic station buildings, and most notably, it's ticket halls.
It is couloured brown on the tube map.
===Central Line===
The Central line is a London Underground line, coloured red on the tube map. It is a deep-level "tube" line, running east-west across London, and, at 76 km (47 mi). It is the longest Underground line and also the busiest with around 260 million passengers a year. Of the 49 stations served, 20 are below ground. It is considered to be the tube line with the highest point-to-point speeds on the Underground, reaching 70 mph (110 km/h) when the 1992 Stock was introduced.
The Central Line is coloured red on the tube map
Circle Line
The Circle Line or Inner Circle is a line on the London Underground. Originally it was a complete circle and theoretically passengers could go round forever, but now it has been remodeled. It shares most of its track and all of its stations with other lines, primarily the Hammersmith & City Line and the District Line.  The strangest station is Edgware Road. It uses C Stock but will soon use S Stock.
It is coloured yellow on the tube map.
===District Line===
The District line is a line of the London Underground, coloured green on the Tube map. It is a "sub-surface" line, running through the central area. It is the busiest of the sub-surface lines. Two of the four (Richmond and Wimbledon) western branches of the route are also the only lines.
Across the entire network to cross the Thames by bridge and not by tunnel. Although the District line is only the fourth longest line on the network, it serves more stations than any other line (60). It is very dense and is built with lots of weirdo branches and lots of stations. It uses D stock (and a tiny bit of C Stock on one Branch) to run. the D and C stock are due to be replaced by the S Stock soon
Hammersmith & City Line
The Hammersmith & City line is a London Underground service on its sub-surface network. Coloured salmon pink on the tube map, the line serves 29 stations in 15.8 miles (25.5 km). Extending from Hammersmith in the West in Zone 2, between Paddington and East Aldgate, the line runs through Zone 1, and to the east extends to Barking in Zone 4. Most of the route and all of the stations are shared by the District, Circle and Metropolitan lines. Together with the Circle line over 114 million passenger journeys are made each year.
The first section opened in 1863 when the Metropolitan Railway began the world's first underground railway service between Paddington and Farringdon Street with wooden carriages and steam locomotives.
The following year a railway to Hammersmith was built jointly by the Great Western Railway and Metropolitan Railways, and the line was extended to the east in stages, reaching the East London Line in 1884. The line was electrified in 1906 and after the London Passenger Transport Board was formed in 1936 some Metropolitan Hammersmith & City line trains were extended to Barking over the District Railway. The Hammersmith & City line was shown on the tube map as part of the Metropolitan line until 1990 when it appeared as a separate line.
The signalling system is being upgraded and the current C Stock trains are to be replaced by new 7-car S Stock trains by 2015.
===Jubilee Line===
The Jubilee line is a line on the London Underground. It originally followed the Metropolitan line for a while, and then broke off, terminating at Charing Cross station. Nowadays, however, it no longer stops at Charing Cross at all, instead heading through the south of London and then rearing up to terminate at Stratford in north - east London.
The Jubilee line is coloured grey on the Tube map.
===Metropolitan Line===
The metropolitan line is a sub surface line on the London Underground. It is the oldest line, and the original version linked Paddington and Farringdon. Nowadays it is huge and is the only sub surface line to go outside of the Greater London county. It uses S stock but did use A stock until recently. Originally the Hammersmith and City Line and East London Line were also part of the Metropolitan line but nowadays are not.
===Northern Line===
The Northern line is a line on the underground railway system, London Underground. It is coloured black on the Tube map.
It is mostly underground (deep level) and serves the southernmost and some of the northern most stations, running complex north south with branches arrangement because originally it was built by lots of companies. On par with the Jubilee line it is the deepest line. It uses similar stock to the jubilee line as well (1955/ 1956 Stock).
===Piccadilly Line & Heathrow Circle===
the Picciadilly line is an underground line running from north to south-western london, and also serving Heathrow airport.
It is coloured blue on the tube map.
The Heathrow Circle is a circle of railway serving Heathrow terminals 123, 4, & 5. It is on the Piccadilly Line of the London Underground.
===Victoria Line===
The Victoria line is a deep-level London Underground route running from the south (fare Zone 2) to the north-east (Zone 3) of London. It is coloured light blue on the Tube map. It runs only underground except for the Depot. It is so named because of it serving Victoria station.
It is the sixth most used line but the most intensively used line (journeys per mile) and is quite high tech, using very new trains (2009 Stock) and special humpback stations that save energy.
The only station on the Victoria line to have no form of rail interchange is Pimlico, though Brixton tube station is a separate building from its National Rail neighbour.
===Waterloo & City Line===
The W&CL is a line on the tube network, most notably the smallest, and also the only one to have no track above ground, or indeed, any connection to above ground tracks (Unlike the Victoria Line, with a depot on the surface.
It is coloured teal on the tube map. 
==Trivia==
The name originally only meant or described the tubey circular lines that were deep level as opposed to the sub surface ones that were built way earlier and ran on steam. Nowadays, it often refers to the whole system.
==See Also==
*London Overground
*The DLR
*Croydon Tramlink
*Emerates Air Line
Category:London Underground
Category:European Railways
Category:Subway Systems
Category:Companies
Category:United Kingdom