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The Hogsmill River in Surrey, is one of the tributaries of the River Thames. It rises in Ewell and flows into the Thames at Kingston upon Thames on the reach above Kingston road bridge. The river is 6 miles in length and has a catchment area of 73 km². The river flows through low-lying land, most of it sports grounds and green space, with the exception of Kingston town centre.
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Starting at the Thames at Erith and finishing on the opposite north bank at Coldharbour, the Loop (London Outer Orbital Path) is 150 miles long, passing through numerous woods, commons and parks and on waterside paths alongside the Grand Union Canal and London rivers such as the Colne, Crane, Cray, Darent and Ingrebourne.