London–Aylesbury line Aylesbury and by platform extensions up to Stoke Mandeville. In 1961 LT withdrew the Metropolitan line from Aylesbury and since then it goes only as far as Amersham. Following the end of steam-hauled Metropolitan line trains in 1961 the service was provided by British Rail Class 115 diesel multiple units until 1992 (which were then replaced by the line's current rolling stock) - along with Metropolitan line electric multiple units south of Amersham. Responsibility for the line north of Amersham was transferred from London Transport to British Railways on 11 September 1961; London Underground signage at the stations on this
Art on the Underground Art on the Underground Art on the Underground, previously called "Platform for Art", is a visual arts showcase sponsored by London Underground, the rapid transit system for London, England. London Underground's associations with visual art began in 1908 when its then Publicity Officer Frank Pick began commissioning leading artists to work on poster campaigns for the rapidly expanding network. The company's distinctive corporate image, including official Underground roundel and iconic tube map designed by Harry Beck are also considered major contributions to visual art, and several of the network's stations have been decorated with artistic tiling or murals depicting local