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
London Underground infrastructure were originally maple wood, then aluminium from 1963, and this had been replaced with plastic or rubber following an increase in serious injuries following falls. However, following the King's Cross fire, aluminium treads have been used. 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 across the Underground, with 72 stations having step-free access from street to train. Major efforts have taken place to improve accessibility across the Underground, with the Jubilee line extension having lifts from opening