LONDONUNDERGROUND
London Underground
The London Underground is a public metro system serving a large part of Greater London and parts of the counties of Buckinghamshire, Hertfordshire and Essex. The system serves 270 stations and has of track, 55 per cent of which is above ground. The network incorporates the world's first underground railway, the Metropolitan Railway, which opened in 1863 and is now part of the Circle, Hammersmith & City and Metropolitan lines; and the first line to operate underground electric traction trains, the City & South London Railway in 1890, now part of the Northern line. The network has expanded to 11 lines, and in 2012/13 carried over 1 billion passengers.The above text is a snippet from Wikipedia: London Underground
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