London Underground ticketing destinations and most interchange stations are in zone 1, meaning that most journeys over similar distances will cost the same. A few stations in the north east of the network, on the Central line, outside Greater London (in the Epping Forest district) are in zones 4, 5 and 6. In the north west of the network, on the Metropolitan line, zones 7, 8 and 9 (formerly A - D) cover stations outside Greater London including Amersham and Chesham in the Chiltern district of Buckinghamshire. Unlike the lower numbered zones, these ancillary areas do not encircle the capital. Some stations are
History of the London Underground were first installed at Earl's Court between the District and Piccadilly line platforms, and at all deep level tube stations after 1912. The last, the Charing Cross, Euston & Hampstead (the Hampstead) opened in 1907, and ran from to Camden Town, before splitting into two branches going to Golders Green and Highgate (now Archway). To promote travel by the underground railways in London a joint marketing arrangement was agreed that included maps, joint publicity and through ticketing. UD signs were used outside stations in Central London. The UERL acquired London bus and tram companies in 1912 and the following year