River Colne, Hertfordshire

The Colne is a river in England which is a tributary of the River Thames. It flows mainly through Hertfordshire and forms the boundary between the South Bucks district of Buckinghamshire and the London Borough of Hillingdon. It splits off into several separate branches, some of which rejoin it, and it flows into the River Thames on the reach above Penton Hook Lock at Staines-upon-Thames.

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