London Underground with smaller trains that run in two circular tunnels ("tubes") with a diameter about . These lines have the exclusive use of a pair of tracks, except for the Piccadilly line, which shares track with the District line between Acton Town and Hanger Lane Junction and with the Metropolitan line between Rayners Lane and Uxbridge; and the Bakerloo line, which shares track with London Overground services north of Queen's Park. Fifty-five per cent of the system runs on the surface. There are of cut-and-cover tunnel and of tube tunnel. Many of the central London underground stations on deep-level tube routes
London Colney London Colney London Colney () is a village and civil parish in Hertfordshire, England. It is located to the north of London, close to Junction 22 of the M25 motorway. It is near St Albans and part of the St Albans District. At the time of the 2001 census the population of London Colney ward was 7,742, increasing to 9,507 at the 2011 Census. It is considered a satellite or dormitory village of St Albans, where some villagers travel to work and shop. The civil parish was formed in 1947 from part of St Peter Rural. London Colney Primary School