Freshwater Redoubt was constructed between 1855 and 1856 to protect the Freshwater Bay Beach which it overlooked. A deep dry moat was cut to protect the landward approaches, with a large caponier to provide flanking fire. The cliff protected the sea side of the Redoubt.
The Lower Battery covered the beach with three 8-inch SB howitzers when built. This was remodelled in 1891 to mount two 6-pdr QF and a single Maxim machine gun. A single pivot and racer for one of the old 8-inch howitzers survived between the two new 6-pdr mounts.
Upper (South) Battery of four guns faced South. Initial armament was four guns, with a 7-inch RBL on each salient and two 64-pdr RML guns in the centre. The East Salient 7-inch RBL emplacement survives but the other three gun positions have now been lost. In 1893 the &-inch guns were removed, and the battery prepared to mount two 4.7-inch guns but the idea was dropped five years later. The Upper Battery was then used as a training battery with two 12-pdr and three 6-pdr QF guns.
The Caponier has recently been rebuilt as part of a private residence.