Westerdale is a scattered crofting village which lies on the River Thurso, located 5 mi directly south of Halkirk, in Caithness, Highland, Scotland. The B870 road passes through the village. The 14th century Dirlot Castle is located 3 mi south of the village, and was the stronghold of the Sutherlands, Cheynes, Gunns and Mackays throughout its history.