The Maunsell Sea Forts

These striking structures were built during the Second World War to defend the Thames Estuary from attack by the Luftwaffe. Located six miles off the coast of Whitstable and Herne Bay, Kent, they're isolated and lonely places. Decommissioned by the military in the 1950s, they were used by pirate radio stations for a few years in the sixties and seventies, but now stand abandoned.