Highgate tube station is in the North of London but once there was a high-level station on the surface above it. This station was opened in the 1860s and at one stage was planned to be a grand hub for local services in London's Northern suburbs but Post-War austerity and changes of plan meant the station and the lines it served withered and the station closed in 1954.
I went on a tour of the remains of the high-level station on Thursday as part of the Hidden London series. The platform buildings remain but much of the station area has now been reclaimed by nature, including some of the tunnels next to the station which are bat sanctuaries. You can see my photos here.