Citadel

After the pirate Barbarossa rampaged through in 1544, murdering most of Lipari's men and enslaving the women, the island's Spanish overlords fortified Lipari by constructing a citadel (also known as the castle) around the town centre. The town has since moved downhill, but much of the citadel's impregnable wall structure survives; it's an impressive sight, especially when seen from below.