Rapid transit system serving Britain's capital and parts of…

Rapid transit system serving Britain's capital and parts of neighbouring counties, and the oldest of its kind in the world. Its first section, the Metropolitan Railway, opened in 1863 between Paddington and Farringdon using steam locomotives. Nicknamed the Tube after its deep circular tunnels, it has eleven lines shown on Harry Beck's famous diagram map. Passengers are reminded to mind the gap, and its red roundel logo is instantly recognisable.

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