Fréjus Road Tunnel in the context of "Fréjus Rail Tunnel"

The Susa Valley (Arpitan: Vâl Susa; Piedmontese: Valsusa; Occitan: Val d'Ors; Italian: Val di Susa; French: Val de Suse) is a valley in the Metropolitan City of Turin, Piedmont region of northern Italy, located between the Graian Alps in the north and the Cottian Alps in the south. It is one of the longest valleys of the Italian Alps. It extends over 50 kilometres (31 mi) in an east-west direction from the French border to the outskirts of Turin. The valley takes its name from the city of Susa which lies in the valley. The Dora Riparia river, a tributary of the Po, flows through the valley.

A motorway runs through the valley from Turin to Chambéry in France through the Fréjus tunnel or by crossing the Col du Mont Cenis (2083m), and to Briançon, also in France, over the Col de Montgenèvre.

The Cottian Alps (/ˈkɒtiən ˈælps/; French: Alpes Cottiennes [alp kɔtjɛn]; Italian: Alpi Cozie [ˈalpi ˈkɔttsje]) are a mountain range in the southwestern part of the Alps. They form the border between France (Hautes-Alpes and Savoie) and Italy (Piedmont). The Fréjus Road Tunnel and Fréjus Rail Tunnel between Modane and Susa are important transportation arteries between France (Lyon, Grenoble) and Italy (Turin).