London Underground and the mechanisms are regularly degreased to lower the potential for fires. The only wooden escalator not to be replaced was at Greenford station, which remained until October 2015 when TfL replaced it with the first incline lift on the UK transport network. There are 426 escalators on the London Underground system and the longest, at , is at Angel. The shortest, at Stratford, gives a vertical rise of . There are 184 lifts, and numbers have increased in recent years because of investment making tube stations accessible. Over 28 stations will have lifts installed over the next 10 years,
Oval tube station N133, N136 and N155 serve the station. The station was mocked up by the 14-21/04/76 BBC1 series "Survivors: The Lights of London parts 1 & 2". However, the filmed site was actually at Camden Town deep-level shelter. Oval tube station Oval is a London Underground station in the London Borough of Lambeth. It is on the Northern line between Stockwell and Kennington stations and is in Travelcard Zone 2. It opened on 18 December 1890 as part of the City & South London Railway and is named after The Oval cricket ground, which it serves. The station is located at