|Built 500 metres off the isle of Grain, Kent, UK.|
Originally completed in 1855 and is similar in construction to other Martello towers that can be found around the Kent coast.
The tower was modified in 1910 with the addition of 4.7" quick fire guns to protect ships moored at Sheerness or Chatham from high speed torpedo boats.
The guns were removed in 1929 and then replaced in 1940 with a twin 6 pounder QF.
The rectangular free standing structure you can see next to the tower was added as a barrack block to accomodate the increased compliment required to run the battery.
The battery is reachable by foot during low tide via the slipway that can be seen running to the shoreline.