Rapid transit in the United Kingdom consists of four systems in three cities: the London Underground and Docklands Light Railway, Tyne and Wear Metro and the Glasgow Subway.
The Merseyrail in Liverpool possesses some aspects of a rapid transit system, although is usually referred to as a commuter line.
The United Kingdom is the birthplace of rapid transit, with London and Glasgow hosting the world's first and third urban rail transit. From 1893 to 1956 the Liverpool Overhead Railway was the only elevated rapid transit in the country, but fell into disuse. In the 20th and 21st century the United Kingdom has chosen to not prioritise investment in rapid transit schemes; instead cities like Manchester, Sheffield, and Edinburgh have opted for light rail systems.