At the same time as the breakwater was being built in the 1850s, the island was fortified by a string of 13 forts, designed to protect the harbour of refuge. The accommodation quarters of several of the forts have been converted into apartments; two are now private homes; and one, Fort Clonque, at the end of a causeway that can be flooded at high tide, belongs to the Landmark Trust and can be rented for holidays. Scenes from the film "Seagulls Over Sorrento" were shot at Fort Clonque in 1953.