Scrabster Castle[a] was a castle, near Burnside, about 0.5 miles (0.8 km) north and west of Thurso, and 0.5 miles (0.8 km) south of the village of Scrabster, Highland in Scotland, south of Thurso Bay.

Bishop John of Caithness was mutilated by Harald Maddadsson, Mormaer of Caithness, in 1201,[3] after being besieged at the castle, having his tongue and eyes removed for John's refusal to collect Peter's Pence, a tax of 1/10 of the income of every freeman.

George Sinclair, 4th Earl of Caithness, seized the castle in 1544.

While erosion has partly destroyed the curtain wall, with other parts obscured by turf banks, short stretches of the outer face are exposed.

The inner wall-face of a building about 5 metres (16 ft) square with a mural chamber is visible.