History of the London Underground and was followed by 1959 tube stock. After experiments with an AEC lightweight diesel multiple unit in 1952, steam trains were removed from the Central line following the electrification of the Epping–Ongar section in 1957. Between 1963 and 1970, London Transport reported directly to the Minister of Transport, before control passed to the Greater London Council. Electrification work on the Metropolitan line, suspended due to the war, had restarted in 1959. The line was electrified to and the unpainted aluminium (A Stock) replaced steam trains, British Rail providing services for the former Metropolitan line stations between Amersham and . The
Central line (London Underground) Total track length is , of which is in tunnel; this track is electrified with a four-rail DC system: a central conductor rail is energised at −210 V and a rail outside the running rail at +420 V, giving a potential difference of 630 V. The single-track line north of Epping, which closed in 1994, is now the Epping Ongar heritage railway. shuttle services operate on weekends between North Weald and Ongar and North Weald and Coopersale. These do not call at Blake Hall, as the station platform was removed by London Transport after the station closed, and the remaining