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,
History of Sardinia to the north (Sassari) was enhanced (the road still exists today and it still bears the name of Carlo Felice). Also, the first ferry route between the island and Genoa was established, using steamboats such as the Gulnara. The first railway was inaugurated in 1871. By the end of the nineteenth century the Royal Railways had received 30 locomotives, 106 passenger cars, and 436 cargo cars. The economy was focused mainly on the primary sector (agriculture and sheep husbandry) and on mining. The majority of mining societies operating in Sardinia depended on non-Sardinian capital money. However, in 1848 the Sardinian