The castle on the cliff above the sea dates from the early 12th century and consisted of a stone tower protected by a curtain wall. The walls had a gateway and several small towers on the landward side. It was attacked and captured in 1153 by the Welsh. The castle was badly damaged during a seige in the Civil War.
Over the years the town walls took over as the main defence of Tenby. Much of these 13th century walls survive, the most complete in Wales, including a round gateway, the Five Arches Gate, which was one of four entrances to the town.
St Catherine's Fort, built in 1869 as one of the Palmerston defences for Pembroke, is on a rocky outcrop in the middle of the beach below the castle. The fort never took part in any action. It was sold off in 1907, and has been privately owned since, although it is now derelict.
|The castle is to the northeast of the town centre|