During the war, Bull Sandfort could accommodate a garrison of up to 200 naval personnel and it was armed in World War 2 with two 6-inch guns and two 6-pounder guns.
Its smaller companion fort on Haile Sand, located 3.75km to the southwest, guarded the approaches to the Humber with gun batteries and an anti-submarine net of steel mesh that stretched between them across the mouth of the estuary.
Inside, the fort is made up of three floors – the basement and magazine floor is below sea level, while there is also a central 2-storey observation tower above water level. A freshwater supply comes from an artesian well.
While the whole premises is in need of refurbishment, the vacant fort features an external balcony and jetty that would provide incredible views of the Humber Estuary.
There is potential for the fort to be refurbished and used for development or alternative uses, subject to consent.
The property is listed by estate agent Savills and the auction is set to take place on 19 July.
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