Central line (London Underground) Hammersmith (Grove Road) railway station. Authorisation was granted in 1920, but the connection was never built, and the L&SWR tracks were used by the Piccadilly line when it was extended west of Hammersmith in 1932. On 1 July 1933, the Central London Railway and other transport companies in the London area were amalgamated to form the London Passenger Transport Board, generally known as London Transport. The railway was known as the "Central London Line", becoming the "Central line" in 1937. The 1935–40 New Works Programme included a major expansion of the line. To the west new tracks were to be
London Underground infrastructure London Underground infrastructure The infrastructure of the London Underground includes 11 lines, with 270 stations. There are two types of line on the London Underground: services that run on the sub-surface network that is just below the surface and use larger trains, and the deep-tube lines, that are for the most part self-contained and use smaller trains. Most of the lines emerge on to the surface outside the central area. The oldest trains running on the Underground were introduced in 1972. The Underground is electrified using a four-rail system, the DC traction supply being independent of the running rails. Planned