King Charles' Castle

King Charles' Castle is a fortification built between 1550 and 1554, constructed from roughly coursed granite rubble. It has a cruciform plan with domestic quarters located at the rear of a semi-hexagonal battery on the west end. Originally designed as a two-storey structure, the fort features gun ports at the center of each of its five sides. The domestic quarters include small square projections to the northeast and southeast of the hall and kitchen, with a guardroom projecting to the east. Notable architectural features include rebated window surrounds, a chamfered two-light stone-mullioned window, and a chamfered pointed-arched doorway with a rebate and draw-bar hole leading to the east guardroom. The large single chamber, which was the former kitchen, contains an oven in the fireplace. The castle was built to protect the entrance to New Grimsby Harbour but was poorly located and later replaced by Cromwell's Castle, from which much of its stone was taken. The site is scheduled as an Ancient Monument.