Deal Castle was built by Henry VIII in 1539, fearing a threat of invasion by the catholic powers in Europe. English Heritage, who maintain the Castle, describe it as "one of the finest Tudor artillery castles in England". The fort guarded the sheltered anchorage of "The Downs" – the stretch of water between the shore and the hazardous Goodwin Sands. Deal Castle is normally open daily from 1 April to 30 September.