St Catherine's Fort

St Catherine’s Fort stands on St Catherine’s Island, a small limestone island joined to the town of Tenby in Pembrokeshire by a causeway uncovered at low tide. Built in the 19th century as part of a chain of coastal defences, it was designed to guard Tenby Harbour and the southern Pembrokeshire coast from invasion. Colonel William Jervois drew up the plans, creating a rectangular fort with gun positions on two sides and additional platforms on the roof. The entrance is protected by a dry ditch and flanking galleries with loopholes for rifle fire. Inside, a powder magazine and shell store sit at the eastern end, while accommodation was provided for 150 soldiers. The fort’s history reflects changing military needs and private ownership. It was sold to a local builder in 1866, built at a cost of £40,000, and completed by 1870 though its guns were not installed until 1886. Later it served briefly as a training post for the Royal Naval Reserve before being sold in 1907. In 1914 it became a private home with lavish interiors, then a zoo from 1968 until 1979. After years of disuse it was restored and reopened to the public in 2017 with help from volunteers. Visitors walk across the causeway at low tide to reach the fort and explore its granite walls and gun emplacements. The restored rooms include the original magazine and shell store, while the roof offers views over Tenby Harbour and the surrounding beaches. A nature trail circles the island, and the fort’s history is explained through simple displays. The island also served as a filming location for a Sherlock episode, adding a modern connection to its past.