Cornelia Battery constructed on Robben Island to guard the Blaauwberg Channel that lies to the north of Robben Island. Built in 1939 as part of the defences to protect the northern entrance to Table Bay. Cornelia Battery mounts two 6-inch BL guns, with underground magazine between the two pits. The basic design is fairly standard for British Coastal Artillery of this time. There is a Fortress Fire Command Tower located to the rear of the Battery. The two searchlights are situated on the foreshore, and local defence is provided by pillboxes.