A rectangular, concrete structure built during the Second World War as part of the Gibraltar Point Coastal Defence Battery (see MLI43285). The exact original function of the structure is not conclusively known, but a storage or shelter usage is thought to be likely. When originally built, the structure had a central entrance opening but no windows. The structure was refurbished shortly after the end of the war, during the winter of 1948-9, when it was converted to be used as a bird observatory for the Gibraltar Point Nature Reserve. {1}