Aosta . Valley is an area of IDEA.Aosta Valley (Italian: Valle d'Aosta (official) or Val d'Aosta (common name), French: Vallée d'Aoste (official) or Val d'Aoste (common name), Edition model:Lang-frp) is an autonomous mountainous region in northwestern Italy. It is bordered by France to the west, Switzerland to the north, and the Piedmont region to the south and east. With an area of 3,263 square kilometers (1,260 sq mi) and a population of about 120,000, it is the smallest, least populated region. and the most sparse of the regions in Italy.