Sardinia is constituted by the homonymous island (after Sicily, the second biggest of the Mediterranean), and by numerous minor islands (San Pietro, Sant’Antioco, Mal di Ventre, Asinara, Isola Piana, Caprera, La Maddalena, Spargi, Budelli, Razzoli, Santa Maria, Tavolara, Molara, Serpentara e Isola dei Cavoli), for a global expansion of 24.090 kilometers square. The population is of over 1,600,000 inhabitants. The regional capital is Cagliari. From 2005 provinces are doubled: from four to eight.
Sardinia, the oldest land on earth, is estimated to be old around 600 millions of years ( it emerged in the Carboniferous: hundreds millions years ago it was in strictly contact with France and Spain, before to carry out a translation with the neighbouring Corse) and boasts a signal stability in its structure: its volcanoes are extincted from millions years. It can’t be said the same about the hydrological viewpoint, a problem that characterizes as well cities like Cagliari: uncountable are the underground caverns of uncommon sizes.
The caves in the island are among the most beautiful and ancient in Italy and in Europe: it is possible to find some of these in the interior and along the coasts alike ( some are reachable only by sea, and some others are visitable only by rigged and capable speleologists). An other phenomenon that involves particularly Sardinia is the erosion, caused by the natural composition of its rocks and by the strong action conducted by the dominant winds.