River Pinn

River Pinn
River Pinn at Ickenham
Source of the Pinn Mid-course River Pinn (London Borough of Hillingdon) Show map of London Borough of Hillingdon Source of the Pinn Mid-course River Pinn (England) Show map of England
Location
Country	England
Region	Greater London
Physical characteristics
Source
• location	51°37′12.5″N 0°20′54.1″W / 51.620139°N 0.348361°W / 51.620139; -0.348361
• elevation	Roughly 120 m (390 ft)
Mouth
• location	51°30′52″N 0°28′48″W / 51.51444°N 0.48000°W / 51.51444; -0.48000
• elevation	31 m (102 ft)
Basin features
Progression	Pinn → Colne → Thames

The Pinn is a suburban, outer west London river. It has dendritic headwaters, the furthest is considered its source – in Harrow Weald. Its confluence with Frays River makes it a tributary of the Colne. It is one of three principal rivers wholly in the historic county of Middlesex.^[a]
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