Couston Castle is a heavily-restored 17th century tower house which stands on the banks of Otterston Loch.

The lands of Colestun, along with Balemacmol and Muntequim, were granted by Robert of London, illegitimate son of William I of Scotland, to Roger Frebern in the late 12th century.

In the mid-13th century Couston was owned by Robert of Rosyth and was part of the barony of Rosyth.

By the late 14th century the lands of Couston had been divided into quarters.

In the 16th century Couston was a possession of the Stewarts of Rosyth, and a James Logan of Couston is on record in the 17th century, a descendant of the Logans of Restalrig. The Logans are thought to have been responsible for remodelling the castle.

By the 1830s the castle was a substantial ruin but a decade later the majority of it was dismantled to provide stone for the building of a farm steading to its east. Only a section of the stair tower with a 17th century doorpiece, and an attached gable end rising to third floor level, were left standing.

The ruins were bought in 1980 by Alastair Harper and the architect Ian Begg was employed to restore and extend them in the style of a 17th century tower house. The castle remains a private home.