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
Upminster (UK Parliament constituency) Hilldene, and Upminster. 1983-1997: The London Borough of Havering wards of Ardleigh Green, Cranham East, Cranham West, Emerson Park, Gooshays, Harold Wood, Heaton, Hilldene, and Upminster. 1997-2010: The London Borough of Havering wards of Cranham East, Cranham West, Emerson Park, Gooshays, Harold Wood, Heaton, Hilldene, and Upminster. Upminster was the easternmost constituency of the London Borough of Havering, and of Greater London. The constituency was oddly shaped and covered both the wealthiest and the poorest parts of the borough while being London's least ethnically diverse constituency. The constituency included the Upminster suburb of Cranham. The boundary to the north extended