Fort Fareham was one of the forts making up the Gosport Advanced Lines t0 provide protection from land attack on Portsmouth Harbour. It was one of the three forts recommended by the 1859 Commission on the Defence of the United Kingdom for this area, the other two fort never being built.
Built between 1861 and 1886 it was approved to be armed with sixty four 7-inch RBL guns. It would appear that there was never more than about seventeen of the these 7-inch RBL guns mounted, seven in Haxo Casemates. By 1892 five positions for Moncrieff Disappearing Guns had been built, probably also with 7-inch RBL guns.
The site was primarily used for barrack accommodation and logistics.