Rousse Battery incorporates Tower Number 11 within it defences. There was initially a coastal defence battery on the beach nearby, which has now been lost. Tower 11 was built by 1779 and was one of the infantry towers with loopholes for musketry. In 1804 a coastal defence battery was built to the front of Tower 11 and the Tower was used as a keep with a perimeter wall across the gorge of the battery. Rousse Battery mounted five guns, three 24-pdr SB and two 9-pdr SB. The gun deck was slabs of Purbeck granite brought in from Dorset, England.
The battery was surrounded by a dry moat to provide additional local defence.
There is a small magazine to the rear of Rousse Battery.