device fort built henry_viii protect threat french attack constructed stone angular design hybrid italian military architectural thinking traditional english military design site raided french force summer fortification constructed site suffered coastal erosion castle demolished history 16th century background built consequence international tensions england france final years reign king henry viii traditionally crown left coastal defences local lords communities taking small role building maintaining fortifications france empire remained conflict maritime raids common actual invasion england unlikely modest defences based simple towers existed south west sussex coast impressive works north england general fortifications limited scale henry broke pope long standing marriage wife catherine resulted france empire declaring alliance henry pope encouraging countries attack england henry responded ordering instruction called device construction fortifications vulnerable parts coast immediate threat passed resurfaced france threatening invasion channel backed allies scotland henry issued device improve country defences particularly south coast construction built april september protect south east coast overlooked bay constructed italian engineer surveyor captain labourers cost designed central courtyard square tower angular circular looking sea rear stone defences protected moat castle wooden pier boats dock angular echoed contemporary italian thinking military architecture influenced king surveyor works continental background despite relatively advanced english fortification castle feature fashionable arrow head design nearby historians describes imperfect hybrid english continental ideas confused modern designs castle completed french attacked admiral crossed channel arrived ships july local authorities feared castle target night attack french soldiers men landed attacked labourers present advance soon stalled french retreated fleet bringing invasion threat end castle finally completed departure 17th century 17th century coastal erosion undermined castle walls charles announced repair fortification instead ruins dismantled sir new fortification built place positioned inland possible remains foundations original castle visible shore low tide
Sandown Castle, Isle of Wight