London Underground infrastructure Tube Programme, investigating replacing the trains for the Bakerloo and Piccadilly lines, is looking for trains with better energy conservation and regenerative braking. The Underground serves 270 stations. Fourteen Underground stations are outside Greater London, of which five (Amersham, Chalfont & Latimer, Chesham, and Chorleywood on the Metropolitan line and Epping on the Central line) are beyond the M25 London orbital motorway. The longest distance between two stations is between Chalfont & Latimer and Chesham on the Metropolitan line. The shortest distance between adjacent stations is the between Leicester Square and Covent Garden on the Piccadilly line. The station furthest
London Underground G Stock London Underground G Stock The G Stock were 50 electric multiple unit train carriages built for the District Railway in 1923 by Gloucester RC&W. They operated on the District line of the London Underground until 1971 (with most cars being withdrawn in the early 1960s). The G Stock was built to allow the scrapping of some of wooden-built B Stock trailer cars which were in poor condition. Some steel-framed B Stock motor cars were converted to trailers, themselves being replaced by new G Stock motorcars. The G Stock consisted entirely of motor cars, all built with a clerestory roof similar