London Post Office Railway

The Post Office Railway, known since 1987 as Mail Rail, is a 2 ft (610 mm) narrow-gauge, driverless underground railway in London that was built by the Post Office with assistance from the Underground Electric Railways Company of London, to transport mail between sorting offices. Inspired by the Chicago Tunnel Company, it opened in 1927 and operated for 76 years until it closed in 2003. A one-kilometre (5⁄8-mile) section of the former railway at Mount Pleasant was opened for passenger use in September 2017 as part of the revamped Postal Museum.