London Underground at +420 V, giving a potential difference of 630 V. On the sections of line shared with mainline trains, such as the District line from East Putney to Wimbledon and Gunnersbury to Richmond, and the Bakerloo line north of Queen's Park, the centre rail is bonded to the running rails. The average speed on the Underground is 20.5 mph. Outside the tunnels of central London, many lines' trains tend to travel at over 40 mph in the suburban and countryside areas. The Metropolitan line can reach speeds of 62 mph. The London Underground was used by 1.379 billion passengers in
London Underground 1967 Stock London Underground 1967 Stock The London Underground 1967 Stock was a type of deep-level tube stock which operated on the Victoria line of the London Underground from when the line first opened on 1 September 1968 until 30 June 2011. Some of the stock was also used on the Central line between Woodford and Hainault between 21 February 1968 and 1984, as the same automatic train operation (ATO) system was used on both lines. A total of 316 cars (39.5 train sets) were built by Metro-Cammell, and the stock was refurbished at Rosyth. Withdrawn cars of Mk I 1972 stock