Fortino di Mazzallakkar: A Ninth-Century Arab Fort Submerged for Six Months

The Fortino di Mazzallakkar, an Arab fort in Sambuca di Sicilia, Sicily, Italy, was built by the Arabs around 830 AD to defend the territory around Sambuca di Sicilia, which was then known as Zabut. For over a thousand years, the fort stood. From the mid-20th century, it was used as a shelter for livestock. In the 1950s, the Carboj dam was built, causing the waters of Lago Arancio to rise and submerge the fort for six months of every year, causing damage. Today, the fort is privately owned and can be visited on request, but its walls still stand, slowly crumbling. Originally, it had a square shape, with a circular tower on each corner. Each tower had a limestone dome and was equipped with slits. The walls were up to 4 meters (13 feet) high.

Sources: Wikipedia, OpenStreetMap, Wikidata, Wikimedia Commons