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The London Underground system is also known as the "Tube". It is the oldest underground system in the world, the first section dating from 1863. The present system has over 250 miles of track and 272 stations. There are 11 lines covering Greater London, Essex, Buckinghamshire & Hertfordshire. Nearly half the system is above ground.
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Oxford Circus is a London Underground station serving Oxford Circus at the junction of Regent Street and Oxford Street, with entrances on all four corners of the intersection. The station is an interchange between the Bakerloo, Central and Victoria lines. It is the busiest rapid-transit station in the United Kingdom, with 98.51 million entries and exits in 2014. On the Central line it is between Bond Street and Tottenham Court Road, on the Bakerloo line it is between Regent's Park and Piccadilly Circus, and on the Victoria line it is between Green Park and Warren Street. The station is in Travelcard Zone 1.
The Central line station opened on 30 July 1900, and the Bakerloo line station on 10 March 1906. Both are Grade II listed. The station was rebuilt in 1912 to relieve congestion. Further congestion led to another reconstruction in 1923. To accommodate additional passengers on the Victoria line, a new ticket hall was built. The Victoria line station opened on 7 March 1969, including cross-platform interchange with the Bakerloo line.