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 the outer orbital motorway (the M25, outside the built-up area) encircle the city and are intersected by a number of busy radial routes—but very few motorways penetrate into inner London. A plan for a comprehensive network of motorways throughout the city (the Ringways Plan) was prepared in the 1960s but was mostly cancelled in the early 1970s. The M25 is the second-longest ring-road motorway in Europe at long. The A1 and M1 connect London to Leeds, and Newcastle and Edinburgh. London is notorious for its traffic congestion, with the average speed of a car in the rush hour being .