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
West London Orbital West London Orbital The West London Orbital is a proposed extension to the London Overground that makes use of a combination of existing freight and passenger lines including the Dudding Hill Line, North London Line, and the Hounslow Loop. The route runs for approximately 11 miles from West Hampstead and Hendon at the northern end to Hounslow at the Western end via Brent Cross West, Neasden, Harlesden, Old Oak Common, Acton and Brentford. The route would improve rail connectivity across West and North London, and establish a number of new connections to existing radial rail infrastructure including Thameslink, the Jubilee