Italy, officially the Italian Republic or the Republic of Italy, is a unitary parliamentary republic in south-central Europe. To the north, it borders France, Switzerland, Austria and Slovenia along the Alps. To the south, it consists of the entirety of the Italian Peninsula, Sicily, Sardinia–the two largest islands in the Mediterranean Sea–and many other smaller islands. The independent states of San Marino and the Vatican City are enclaves within Italy, whilst Campione d'Italia is an Italian exclave in Switzerland. The territory of Italy covers some 301,338 km2 (116,347 sq mi) and is influenced by a temperate seasonal climate. With 60.6 million inhabitants, it is the fifth most populous country in Europe, and the 23rd most populous in the world.