The fortifications of Kotor are an integrated historical fortification system that protected the medieval town of Kotor containing ramparts, towers, citadels, gates, bastions, forts, cisterns, a castle, and ancillary buildings and structures. They incorporate military architecture of Illyria, the Byzantine Empire, Venice, and Austria. Together with the old town and its natural surroundings the fortifications were inscribed in the list of World Heritage Sites in 1979 labelled Natural and Culturo-Historical Region of Kotor and represent the only such site of cultural significance in Montenegro.