With an area of 3,263 km2 (1,260 sq mi) and a population of about 126,933, it is the smallest, least populous, and least densely populated region of Italy. It is the only Italian region which has no provinces (the province of Aosta was dissolved in 1945). Provincial administrative functions are provided by the regional government. The region is divided into 74 comuni (communes).
Italian and French are both official, though the native population speaks also Valdôtain, a form of Franco-Provençal (Arpitan), as home language.
The Commune of Bionaz (French: Commune de Bionaz; Italian: Comune di Bionaz; known during the years 1939–46 as Biona) is a sparsely populated municipality which extends over 143 km² of the Valpelline area of the Aosta Valleyregion of northwest Italy. The commune lies on the left side of the river Dora Baltea. The population of c. 240 is dispersed among twenty or more small alpine villages and hamlets including Biona itself, which is the main centre and capoluogo. The commune belongs to the Comunità Montana Grand Combin.