[1][2] The two forts were planned in 1914, at the start of the First World War, to protect the sea entrance to the Humber Estuary.
During this time, they installed submerged netting to prevent enemy submarines from travelling up the estuary to Hull or Grimsby.
It is a 4-storey concrete building with 12-inch (300 mm) of armour on the seaward side, and originally armed with four 6-inch guns.
[1][4] In 1997 it was sold to the Streetwise Charitable Trust, who intended to restore the fort for use as a drug rehabilitation facility.
[8] In July 2022, it was listed for sale by auction, with a guide price of £50,000, through Savills estate agents.