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
London Underground requiring smaller letters and arrows. Harry Beck had the idea of expanding this central area, distorting geography, and simplifying the map so that the railways appeared as straight lines with equally spaced stations. He presented his original draft in 1931, and after initial rejection it was first printed in 1933. Today's tube map is an evolution of that original design, and the ideas are used by many metro systems around the world. The current standard tube map shows the Docklands Light Railway, London Overground, Emirates Air Line, London Tramlink and the London Underground; a more detailed map covering a larger