London Underground D78 Stock total of five 3-car sets, to be built as BMMUs, in June 2018. London Underground D78 Stock The London Underground D78 Stock, commonly referred to as D Stock, was a type of sub-surface rolling stock which operated on the District line of the London Underground, except on the Wimbledon to Edgware Road service. Following the withdrawal of the C Stock in June 2014, these were the oldest subsurface trains in service on the London Underground. The first units were withdrawn in January 2015 with the last withdrawn on 21 April 2017. The D stock was ordered in 1976 to replace
Wimbledon, London Queen's Road and Wimbledon Bridge. The architects were Bradshaw Gass & Hope. By the 1930s, residential expansion had peaked in Wimbledon and the new focus for local growth had moved to neighbouring Morden, which had remained rural until the arrival of the Underground at Morden station in 1926. Wimbledon station was rebuilt by the Southern Railway with a simple Portland stone facade for the opening of a new railway branch line from Wimbledon to Sutton in 1930. Damage to housing stock in Wimbledon and other parts of London during the Second World War led to a final major building phase,