In 1854 Roselle Battery mounted seven guns, with six guns facing North and the last one in a circular position overlooking the harbour and breakwater. There was a guard room and magazine, and the battery was linked to the nearby Fort Albert by a covered way. This was the primary battery defending the entrance to the harbour.
In about 1900 work began on converting the battery to a 12-pdr Q.F. Battery with two guns. Two Defence Electric Lights were also built on the headland to the front to provide night illumination. Work was completed by 1902. In Fort Albert itself, two 6-inch BL guns were mounted in the Citadel Battery.
In 1913, what was described as a blockhouse (pillbox), was built to provide an infantry defence position on the headland by the Defence Electric Lights.