The Central London Railway (CLR), also known as the Twopenny Tube, was a deep-level, underground "tube" railway that opened in London in 1900. The CLR's tunnels and stations form the central section of the London Underground's Central line.

Liverpool Street station, also known as London Liverpool Street, is a major central London railway terminus and connected London Underground station in the north-eastern corner of the City of London, in the ward of Bishopsgate Without. It is the terminus of the West Anglia Main Line to Cambridge, the Great Eastern Main Line to Norwich, commuter trains serving east London and destinations in the East of England, and the Stansted Express service to Stansted Airport.