Circle line (London Underground) with the other London Underground sub-surface lines: the Hammersmith & City line from Hammersmith to just before Aldgate; the Metropolitan line from Baker Street to Aldgate; and the District line from Tower Hill station to Edgware Road station. The line is electrified with a four-rail DC system: a central conductor rail is energised at and a rail outside the running rail at , giving a potential difference of . The running rails are not electrified. Much of the double track railway from the Hammersmith terminus to Westbourne Park station is on a high brick viaduct. East of Westbourne Park the
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