Synonyms of stronghold

1 Syllable
keep, fort, château
2 Syllables
towers, outwork, castle, bastion, bastions, tower, donjon, redoubt, bulwark, fastness, fortress, fasthold
3 Syllables
citadel, minaret, garrison, garrisons, refuge, defense, citadels, safehold, presidio
5 Syllables
fortification, fortifications