The River Doon (Scottish Gaelic: Abhainn Dhùin, pronounced [avɪɲˈɣuːɲ]) is a river in Ayrshire, Scotland. The river flows 23 miles (37 km) from Loch Doon, joining the Firth of Clyde just south of Ayr. Its course is generally north-westerly, passing near to the town of Dalmellington, and through the villages of Patna, Dalrymple, and Alloway, birthplace of Robert Burns. The source of the Doon is Loch Enoch, high in the Galloway Hills.
In the 1930s the Loch Doon was dammed to provide water to the Galloway Hydro Electric Scheme, today operated by Scottish Power.
The Doon is mentioned in Burns' classic narrative poem "Tam o' Shanter", along with the Brig o' Doon, which spans 72 ft (22 m) across the river, just outside Alloway. The river is also the major setting for his lesser-known poem "The Banks O' Doon".
Coordinates: 55°26′22″N 4°39′00″W / 55.43944°N 4.65000°W / 55.43944; -4.65000