The Hammersmith & City line is a subsurface London Underground line, coloured salmon pink on the London Underground Map, connecting Hammersmith in west London and Barking in east London. Formerly part of the Metropolitan line, it includes the oldest underground railway in the world. The section between Paddington and Farringdon, which opened on 10 January 1863, was the initial part of the London Underground.
The original Hammersmith & City line opened on 13 June 1864, although Hammersmith station itself moved to a different location in 1868. With the exception of the two-stop Waterloo & City line and the East London Line (which is now a London Overground service), it has been the least used line on the Underground. It ranks 10th of the 11 lines in passenger numbers. Out of the 29 stations served, 10 have Hammersmith & City line platforms that are wholly or almost wholly below ground, all in1 cut-and-cover, while those at Paddington, Edgware Road, Farringdon, Barbican and Whitechapel are in cuttings or under train-sheds albeit below street level.
The current Hammersmith & City line was originally a branch of the Metropolitan line until 1988, though in later years it was usually operated as a separate line, with the sections not used by regular Metropolitan line trains (from Hammersmith to Baker Street and from Liverpool Street to Barking) not included on the main Metropolitan line maps. This is also reflected in the line's use of C Stock as opposed to the A Stock used on the 'main' Metropolitan line.
The name Hammersmith & City derives from the Hammersmith and City Railway (H&CR), the 5km section between Hammersmith (Grove Road) railway station and Westbourne Park that opened in 1864, which was built and operated jointly by the Metropolitan and Great Western Railways until 1868. Though now part of the Underground network, this section is an elevated railway, largely built on brick arches and bridges.
Because the name change of the route to the separate identity of the Hammersmith & City line is relatively recent, there are many stations with tiling or enamel maps that still show that they are served by the Metropolitan line, e.g. Bromley-by-Bow station, shared by the H&C and the District line. The Metropolitan line no longer has any interchange with the District.
All Hammersmith & City line trains are in the distinctive London Underground livery of red, white and blue and are formed of C Stock. The line shares trains with the Circle and District (Wimbledon-Edgware Road branch) lines. Starting in 2011, the C Stock used on the Hammersmith & City and Circle lines will be replaced by new S Stock trains, which will also replace the District line's D Stock and the Metropolitan line's A Stock.
There is one depot, Hammersmith, which is located close to the Hammersmith station. However, that depot can only do minor work and other work may be done at the Neasden Depot.
- London Underground Key Facts. Transport for London. Retrieved on 2008-05-21.