Super Outer Circle

The Super Outer Circle was a railway route in London operated 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').

More information on the Wikipedia page.

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