The ruins became a popular spot for picnics in the 18th and 19th centuries, and was painted by J. M. W. Turner. Plans to redevelop the castle as a Martello tower or as a clubhouse for a local golf course came to nothing, although the property was used in the Second World War, probably as an early warning site. Archaeological interest in the fort increased after the war and in 1967 it was taken into the guardianship of the state, the property being bought from the private owners in 1977. It is now operated by English Heritage, who reopened it to visitors after an extensive programme of conservation between 1968 and 1994. The fort is an unusual example of an unmodified Device Fort and is protected under UK law as a Grade I listed building.