Cottian Alps is a mountain range in the southwestern part of the Alps. They form the border between France and Italy. The area is divided administratively between the Italian province of Cuneo and the Metropolitan City of Turin (the eastern slopes), and the French departments of Savoie, Hautes-Alpes and Alpes-de-Haute-Provence (the western slopes). The Cottian Alps are drained by the rivers Durance and Arc and their tributaries on the French side; and by the Dora Riparia and other tributaries of the Po on the Italian side.
The Fréjus Road Tunnel and Fréjus Rail Tunnel between Modane and Susa are important transportation arteries between France and Italy.