Also known as Torre dello Sperone (Espero Reyal), Torre Sulis takes its name from the Cagliari-born revolutionary Vincenzo Sulis, who spent twenty-two years of his life in solitary confinement inside the tower. Built in the first half of the 16th century, it was one of the bastions of the Alghero fortification and was also one of the most majestic towers in the city.