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 into the fire led to the resignation of senior management of both London Underground and London Regional Transport. To comply with new safety regulations issued as a result of the fire, and to combat graffiti, a train refurbishment project was launched in July 1991. In April 1994, the Waterloo & City Railway, by then owned by British Rail and known as the Waterloo & City line, was transferred to the London Underground. In 1999, the Jubilee line was extended from Green Park station through Docklands to Stratford station, resulting in the closure of the short section of tunnel between Green