An 18,000-year-old phalanx was uncovered at this region’s archaeological site of Corbeddu cave. This region’s Arzachena and Ozieri cultures preceded a civilization that built megalithic graves called “giant's tombs.” Structures called Domus de Janas were built in this region prior to a civilization that constructed giant stone towers including one at Santu Antine. Circular (15[1])fortresses called nuraghe were constructed in this region, lending its name to this region’s Nuragic civilization that interacted with the (*) Phoenicians. A 238 BC invasion of this island targeted the provincial capital of (-5[1])Caralis, which would become Cagliari. After this island was conquered by the Romans, an ancient Roman province grouped this island with nearby Corsica. (10[1])For 10 points, name this Italian island, the second-largest in the Mediterranean. (10[1])■END■