The Province of Ogliastra has a surface area of 1,854 square km, with a total population of a little over 55,000 inhabitants, the largest centers being Tortoli', Lanusei, Barisardo, Baunei, being the elast populated Province in Italy. It is administratively divided into 23 Municipalities. The name derives from the number of thousand-year-old olive trees in the area of Santa Maria Navarrese. The territory is mostly mountainous, and there are the two lakes formed by the Flumendosa stream.
The province was recently (May 2005) re-established, though it was one of the 15 Prefetture established in Sardinia, with capital Tortolì, though in 1821 the capital was moved to Lanusei. With the unity of Italy in 1859 the region was divided in only two provinces (Cagliari and Sassari) and Ogliastra was included in the province of Cagliari, to be included again in 1927 into the newly established province of Nuoro.