Site of a Second World War heavy anti aircraft (Diver) battery in the Diver Fringe at North of Grain Fort. It was armed with four 3.7-inch Mark IIc guns equipped with Predictor AA No.10 Mark 1, and Radar AA No.3 Mark V when it was deployed here in March 1945. It was manned by 419 Battery of 138 Anti Aircraft Artillery Regiment. It formed part of the 28 Heavy Anti Aircraft Brigade deployment between Sheppey and Orfordness (1)

The Isle of Grain was surveyed and mapped from aerial photographs as part of the English Heritage: Hoo Peninsula Landscape Project. Despite using war-time aerial photographs, this site could not be identified. These Light Anti Aircraft (LAA) Diver sites were typically rapidly put into action and left very little trace once removed. (2)

<1> Dobinson, C., Operation Diver : England's Defence Against the Flying Bomb, June 1944-March 1945 (Monograph). SWX23707.

<2> English Heritage, 2013, Hoo Peninsula, Kent: Hoo Peninsua Historic Landscape Project (Unpublished document). SKE29515.