Humber Forts
United Kingdom
The Humber Forts are two large fortifications in the mouth of the Humber Estuary in northern England: Bull Sand Fort (53°33′43″N 0°4′3″E) and Haile Sand Fort (53°32′4″N 0°2′1″E).
Fort data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).