Thousands of circular forts dating from 1500 BC are scattered around Sardinia, although this is probably a quarter of the number originally built. These unusual, truncated cones were renovated in Roman times, but little else is known about them. The largest is Su Nuraxi in Barùmini, which rises to three stories. The structures have come to represent the mystical spirit of the island.
The nuraghe (Sardinian: [nuˈɾaɣɛ], Italian: [nuˈraːɡe]; plural: Logudorese Sardinian nuraghes, Campidanese Sardinian nuraxis [nuˈɾaʒizi], Italian nuraghi), or also nurhag in English, is the main type of ancient megalithic edifice found in Sardinia, developed during the Nuragic Age between 1900 and 730 B.C. Today it has come to be the symbol of Sardinia and its distinctive culture known as the Nuragic civilization. More than 7,000 nuraghes have been found, though archeologists believe that originally there were more than 10,000. Wikipedia