The Citadel Battery was built to the west in 1898 and was equipped with three of the latest 9 inch Breech Loading (BL) guns. The three gun emplacements are in fair condition. It is on the western side of Western Heights reched by a footpath around the perimeter of the defences.
St Martin's Battery dates from 1877 and was equipped with earlier 3 ten inch and 2 six inch Rifled Muzzle Launched (RML) guns. It was re-equipped during the Second World War. It is on the south side of the Heights by a car park and view point.