Castletown, Dorset

Castletown is a small village in Underhill on the Isle of Portland in Dorset. It is located close to Fortuneswell, on the shores of Portland Harbour, and includes a sandy beach, as well as one of Portland's notable highlights; Portland Castle, while the Weymouth and Portland National Sailing Academy is also located nearby.

As with the rest of Portland's villages and settlements, Castletown has been designated as a conservation area, as it is a place of special architectural and historic interest. Underhill, incorporating Castletown and other settlements became designated in 1976 with boundary extensions in 1997 and 2000.