Stronghold

(n.) A fastness; a fort or fortress; fortified place; a place of security.

Thesaurus Entries

acropolis, asylum, bastion, beachhead, bird sanctuary, blockhouse, bridgehead, bulwark, bunker, castle, citadel, donjon, fasthold, fastness, forest preserve, fort, fortification, fortress, game preserve, game sanctuary, garrison, garrison house, harbor, harbor of refuge, harborage, haven, hold, keep, martello, martello tower, mote, motte, peel, peel tower, pillbox, port, post, preserve, rath, redoubt, refuge, safe haven, safehold, sanctuary, snug harbor, strong point, tower, tower of strength, ward