Armament
When completed in 1874, a single tier of armoured casemates and an open battery housed 20 rifled muzzle loading guns of 9, 11 and 12.5 inch calibre. By 1906, these were obsolete and were replaced by breech loading 6 inch and 12 pounder quick firing guns. These served through World War I but were all removed by the 1930s. In May 1940, the 5.5 inch guns were removed from HMS Hood in a refit. A pair of these were installed in specially built casemates on the roof of the fort.
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