Sardinia world (22 centenarians/100,000 inhabitants). Sardinia is the first discovered Blue Zone, a demographic and/or geographic area in the world with an oversize concentration of centenarians and supercentenarians. In 2016 there were 50,346 foreign national residents, forming 3% of the total Sardinian population. The most represented nationalities were: Sardinia's most populated cities are Cagliari and Sassari. The Metropolitan City of Cagliari has 431,302 inhabitants, or about ¼ of the population of the entire island. Eurostat has identified in Sardinia two Functional Urban Areas: Cagliari, with 477,000 inhabitants, and Sassari, with 222,000 inhabitants. Sardinia is one of the five Italian autonomous regions,
Arbus, Sardinia Arbus, Sardinia Arbus is a "comune" (municipality) in the Province of South Sardinia in the Italian region of Sardinia. Located in the southwest coast of the island, Arbus is known for its coastline, the Costa Verde, and for several archeological sites, such as the mines of Montevecchio. With an area of , Arbus is the second largest municipality in Sardinia. Arbus has been inhabited by man since the ancient Neolithic. It includes a mountain district which separates Medio Campidano from the sea. There are numerous "tombe dei giganti" (Giant graves) in the district of Capo Pecora, and in other areas