A ruined 14th-century keep, Braal Castle is located on the left bank of the River Thurso a half-mile (1 km) northeast of Halkirk in the Caithness district of Highland Council Area. Possibly built on the site of an earlier structure, the rectangular tower has three storeys; an unvaulted basement, with a hall above and a modest upper floor. Its entrance was on the first floor, probably accessed by a wooden ladder, and a stair rises within the walls, which are 2.5 to 3m (8 to 10 feet) in thickness. The remains of an entirely ruined hall lie adjacent and both are surrounded by a ditch and there is presumed to have been a barmkin wall.
In 1375, Robert II gave the castle and lands to his son David Stewart along with the Earldom of Caithness. James II granted both the castle and Earldom to Sir George Crichton, Lord High Admiral of Scotland, who enjoyed them only briefly and on his death in 1455 they were given to the Sinclairs. By 1547, both were in the possession of George Sinclair, but the castle later became the property of the Sinclairs of Ulbster, who built the nearby mansion in 1856.
