Underground map

The Tube map is a schematic transport map of the lines, stations and services of the London Underground, known colloquially as "the Tube", hence the map's name. The first schematic Tube map was designed by Harry Beck in 1931. Since then, it has been expanded to include more of London's public transport systems, including the Docklands Light Railway, London Overground, TfL Rail, Tramlink and the Emirates Air Line cable car.

As a schematic diagram, it does not show the geographic locations but rather the relative positions of the stations, lines, the stations' connective relations, and fare zones. The basic design concepts have been widely adopted for other such maps around the world, and for maps of other sorts of transport networks and even conceptual schematics.

A regularly updated version of the map is available from the official Transport for London website. In 2006, the tube map was voted one of Britain's top 10 design icons which included Concorde, Mini, Supermarine Spitfire, K2 telephone box, World Wide Web and the AEC Routemaster bus.

As London's early transport system was operated by a variety of independent companies, there were no complete maps of the network, just for the individual companies' routes. These maps were not typically schematic and were simply the line overlaid on a regular city map. There was no integration of the companies' services, nor was there any co-operation in advertising.

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