Hatherwood Battery was one of the coastal fortifications recommended by the 1859 Royal Commission. Initial plans were for the battery to mount six 68-pdr SB guns, but before it was completed the armament was changed. There was to be one facing battery of three 7-inch RML in the centre, and on each flank two 9-inch RMLs. These were designated A to C Group, from right to left.
In 1873 it was proposed that the three 7-inch RMLs in the centre be replaced by two 12-inch (36 ton) RMLs. By 1886 two 12.5-inch (38 ton) RML guns had been installed in the centre, with two 9-inch RMLs on each flank.
In 1886 a Position Finding Station was built on the Headon Warren that lies behind the battery. This PFS had four cells which have not yet be located.
In 1895 the Battery is confirmed to still mount four 9-inch RMLs and the two 12.5-inch RML. At about this time it was suggested that the 9-inch RMLs in the flanking batteries be replaced with 5-inch BL guns on broadside mounts.
By 1900 two 5-inch BL guns, as a practice battery, had been added.
Parts of the battery are now falling down the cliff, particularly the old 9-inch emplacements.