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 Windmill Views from the top of the windmill include Canary Wharf and the transmitter at Crystal Palace. The windmill is owned and managed by the "Upminster Windmill Preservation Trust", who provide regular tours and school visits. It is open on selected weekends from April to October and participates in the Open House London Weekend and the National Mills Day Upminster Windmill Upminster Windmill is a Grade II* listed smock mill located in Upminster in the London Borough of Havering, England. It was formerly known as Abraham's Mill and was in Essex when built. It has been restored and is a museum