It is 75 m long, 3 m wide, and located at an altitude of 2,882 metres linking the villages of Crissolo in the modern Italian province of Cuneo and Ristolas in the French department of Hautes-Alpes.

The purpose of the Monte Viso Tunnel was to increase trade by allowing a smooth transition to the merchant caravans that needed to cross the barrier imposed by the Alps.

[1] For this reason the work was interrupted in the winter and was completed at the end of the summer of 1480 under the direction of the engineers Martino di Albano and Baldassarre of Piasco, with a total cost of 12,000 florins.

Thus, the Monte Viso Tunnel became soon, as in many other crossings of the territory of northern Italy, a crucial element of a commercial route of extreme importance, so much so that from 1482 the Revello's gabelle recorded an annual transit of over 20,000 sacks of salt,[3] in addition to a variety of other merchandise.

Following the Treaty of Lyon (1601), the Marquisate of Saluzzo, which had defended its independence for more than three centuries, was annexed to the Duchy of Savoy, and therefore the Monte Viso Tunnel lost its strategic importance, seeing alternating occasional openings with long periods of closure.

Access to the tunnel is still occasionally obstructed by rockfalls, but the route is now an established link within the network of mountain paths in the Monte Viso-Queyras-upper Po valley district, as an alternative to crossing the summit of the Col de la Traversette.

The slight slope towards the Italian side favoured a frequent infill with debris carried by the thaw, but this was remedied by the recent installation of an anti-avalanche structure at the French entrance.

It is necessary to consider that at an altitude of 2,882 metres the snow cover is present for about eight months a year, therefore the working times were necessarily concentrated in the summer, but then violent meteorological events may occur.

Since techniques that enabled accurate topographical relief were not known, the attack on the tunnel digging was carried forward probably from only one end, reducing the speed of work.

A little further downstream of the Italian entrance to the tunnel, in a detritic zone called Pian Mait at approximately 2,700 metres of altitude, there are the remains of a small barracks of the Border Guard.