castle castle artillery fort constructed henry_viii hampshire england formed king device programme protect invasion france defend southampton water met castle centre surrounded curtain wall moat initially heavily armed garrison men artillery guns castle continued use years surviving english civil war intact extensively 19th century castle base smuggling fresh fears french invasion led brought use artillery fort large coastal battery constructed alongside older castle boom built controlled castle world war castle primarily base deployed anti submarine patrols english channel guns removed end war probably use france air base called grew size inter war years hosting trophy air races outbreak second world war armed face possible german invasion station continued use war military obsolete finally closed short period use castle opened public english_heritage 1980s restored appearance castle received visitors considers preserved example king henry device forts history 16th century construction castle built consequence international tensions england france final years reign king henry viii traditionally crown left coastal defences local lords communities taking modest 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 catherine catherine aunt took personal insult resulted france empire declaring alliance henry pope encouraging countries attack england invasion england appeared certain response henry issued order called device giving instructions defence realm time invasion construction forts english coastline castle designed protect body water led english channel naval base portsmouth important port southampton castle forts lord admiral decided build improve defences east west constructed narrow spit overlooking deep water channel running southampton temporary defences gun batteries erected interim measure castle built quickly finished end probably reused stone lead recently closed castle initially garrison gunners soldiers lieutenant command captain late heavily armed standards time pieces artillery castle caught fire timber needed repairs required trees sent work carried prompted threat spanish invasion time garrison men 17th 19th centuries early england peace france spain coastal defences received little attention english civil war held parliamentary forces king charles protected strong garrison annual cost parliament considered fortress important kept supplied ammunition unlike local forts parliament kept castle operational probably ongoing role defending early 18th century war spanish succession equipped guns castle new central alterations gun outer wall expansion gatehouse additional set rooms castle captain reports showed castle guns poor condition complained fortification command elderly master gunner improvements probably start revolutionary wars year described castle merely garrison castle store munitions fishing boats volunteer naval vessels counter threat french invasion seven guns added castle arsenal protect french attack end napoleonic wars government took control castle base combat smuggling taking advantage water spit good location position waiting interception vessels middle century officers men stationed 1850s renewed military interest site proposals mount artillery guns plans taken forward noted presence 16th century stone create dangerous splinters event enemy artillery fire landing established castle spit 1880s concerns raised southampton vulnerable french attack small ships armed torpedoes result took castle building boom moved 16th century castle small host gun battery protect boom larger battery built south old castle armed inch pounder quick firing guns supported mounted older castle walls boom managed towers called castle far water pounder quick firing guns turn supported machine guns creation defences ultimately forced nearby yacht club southern end spit years 20th century defensive role continued unchanged castle redesigned allow house castle quick firing guns roof new lighter ladder boom installed years approach replaced plan block boom floating plan proposed castle garrisoned wartime officers men housed nearby fort additional naval personnel needed man support vessels boom built alongside castle house experimental intended support royal naval fleet operating channel particularly suitable surrounding waters coastline relatively quiet calm world war broke military opinions utility shifted considerably decision taken rely primarily gun batteries entrances start conflict boom removed replaced anti submarine nets coast guns removed following year protect new nets training purposes took anti submarine patrols channel german raids started inflict critical damage hours flown aircraft year flown months subordinate air stations created portland cabin built oversee air operations taken use officers mess air station spread spit including occupying battery remaining guns removed probably dispatched line france inter war years taken royal_air_force onwards began housing battery demolished create additional space growing station narrow gauge railway constructed spit parts castle moat provide parking planes twice hosted trophy air races sequence popular international events designed encourage development new high speed technology empire air day events held attracting visitors second world war castle initially defended troops barge equipped inch anti aircraft guns millimetre gun air raid shelters constructed castle moat boats base taking evacuation threat german invasion increased defences expanded pounder quick firing guns placed roof supported additional subordinate batteries built following year south west coast castle damaged war placed care maintenance basis acting way station passing aircraft 21st century war returned duty active air base housing squadrons flying boats took berlin passed built tower castle following year began construct signal station tower complete radar radio facilities opened military obsolete raf station finally closed leased site crown estates castle passed state activity centre station opened alongside castle foot replacement tower constructed years later english_heritage took management castle stripped 20th century additions present appeared including old signal station tower site remains open visitors received visitors castle protected law grade listed building scheduled monument air station recreation centre architecture castle storey circular fortification comprising gatehouse curtain wall predominantly constructed portland stone built 16th century designed carry tiers artillery positioned second floor roof central outer curtain wall additional guns placed roof gatehouse floor considers form preserved example device forts castle surrounded water filled sided moat metres accessed 20th century bridge gatehouse 18th century design based simpler 16th century original gatehouse altered addition brick built buildings southern end probably intended provide additional living space garrison gatehouse leads originally sided courtyard gun round curtain wall wall lowered current height concrete building house dating stretches southern end castle centre castle external diameter metres octagonal lower storey circular walls upper levels originally held accommodation captain garrison heavily redeveloped 19th 20th centuries exterior walls ground level originally store ammunition castle guns basement redesigned 1890s electrical generators installed protected new thicker concrete ceiling originally vaulted stone similar style nearby castle floor restored early 20th century appearance barracks room second floor redeveloped late 19th century form barracks room ceiling incorporating additional early 20th century concrete support gun battery roof pounder gun mounts original gun pounder gun display originally royal naval vessel roof originally flat artillery roof removed
Calshot Castle