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The Midland Railway operated a kind of Super Outer Circle was a railway route in London between 1878 and 1880 over tracks which are now mainly owned by Network Rail but include parts of the London Underground. Although not actually a circle or even a complete circuit, the route circumnavigated the northern and western suburbs of the Victorian capital and the name is used to reflect its similarity to the Inner Circle, Middle Circle and Outer Circle routes (contemporarily the service was referred to by the District Railway as 'the Midland Route').

In 1876 the Midland had negotiated running rights over the District Railway from the London & South Western Railway at Hammersmith to South Kensington. The Midland's main interest was supplying coal to Kensington, and in 1878 it opened coal depots at High Street Kensington Station and West Kensington Station. From 1 May 1878 it also ran a passenger service from Earl's Court Station to St Pancras via Hammersmith, South Acton and the Dudding Hill freight line to Cricklewood Station. Two trains an hour ran until 30 September 1880. The coal depots closed in the 1960s.

More information on the Wikipedia page [1].