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,
Watford tube station Watford tube station Watford tube station is the terminus of a Metropolitan line branch line in the north-western part of London Underground in Zone 7. The station opened in 1925. The station is in the Cassiobury area, on Cassiobury Park Avenue at the junction with Metropolitan Station Approach, close to two of the entrances to Cassiobury Park. It is approximately from the town centre, which is more immediately served by and stations. It is known locally as "Watford Met" to distinguish it from the other Watford stations. The station building was designed by the Metropolitan Railway's architect Charles Walter Clark