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,
Project Republic of Sardinia Project Republic of Sardinia Project Republic of Sardinia (, ProgReS) is a separatist political party in Sardinia, founded in January 2011 following an acrimonious split from Independence Republic of Sardinia (iRS). The party's current secretary is Gianluca Collu, while Carla Carcangiu and Sebastian Madau serve as presidents. In January 2011, after a struggle with Gavino Sale, president of iRS, the iRS faction led by former leader Ornella Demuru, including iRS founding members Frantziscu Sanna and Franciscu Sedda, decided to leave the party and launch a "Republican Constituent Assembly" ("Sa Costituente Repubricana"). In February the new party took the name of