fort Synonyms

fortress bulwark citadel fortification bastion fortify garrison stronghold keep rampart castle fort up donjon redoubt outpost camp bunker blockhouse base stiffen stockade castles strengthen strong fasthold supervacaneous stayer station shield reinforce safeguard sconce secure securement shore up somatist tower supply depot bastille casbah crenellation military post command post foxhole pillbox safehold entrenchment motte and bailey trench turret