S.A.V. S.p.A. (Società Autostrade Valdostane) was established in Aosta on 17 November 1962.

The last diaphragm wall of the Mont Blanc Tunnel had fallen a few months earlier, on 14 August 1962, and was opened to traffic three years later, on 19 July 1965. Just sixteen months earlier, on 19 March 1964, the Great St Bernard Tunnel – the first Alpine road tunnel – had already been opened, thus opening up the north-western sector of the Alps to transalpine connections via France and Switzerland to the heart of Europe.

The first section Torino-Ivrea-Quincinetto – built by ATIVA Autostrada Torino-Ivrea-Valle d’Aosta S.p.A. – was opened in May 1961 after three years of work starting in February 1958, the first step in providing the necessary infrastructure link from Turin to the two international tunnels of Mont Blanc and Great St Bernard.

The Aosta Valley and its road network – at that time based on only two state roads S.S. 26 and 27 as the main crossing points to the borders and on the narrow and partly still unpaved access roads to the side valleys – were insufficiently connected to the rest of northern Italy and especially would be unable to absorb the new flow of traffic from or to Turin, the industrial areas of the rest of Italy and the Mediterranean ports. The motorway made up for this shortfall.

Construction work on the Quincinetto-Aosta motorway began in late 1964. The official start of work was 22 May 1965 with the first blasting of the Hône Tunnel.

The new motorway section was to travel along the valley floor, following the course of the River Dora Baltea, following the shape of the territory, in a bid to make the project as unobtrusive as possible. The first 47 kilometres from Quincinetto to Aosta were completed in five years, which was certainly a short time considering the technical and engineering difficulties to be overcome and the technologies available at the time. The decision was made to operate section by section: the first section, from Quincinetto to Verrès (17.1 km) was inaugurated and opened to traffic on 2 July 1967; this was followed by the Verrès-Châtillon section (11.1 km) on 16 October 1968, the Châtillon-Nus section (11.2 km) on 9 July 1969 and finally the Nus-Aosta Est section (8.5 km) on 25 May 1970.

After several years, the initial project was further expanded with the construction first of the Aosta Bypass (11.6 km) that opened to traffic on 24 December 1994 and, subsequently, with the construction of the motorway link between the A5 and the S.S. 27 Gran San Bernardo, opened in two successive sections: the first functional section (5.6 km) that opened to traffic on 19 December 1997, and the second functional section (2.3 km) that opened to traffic on 5 November 2001.