Cesana Torinese in the context of Montgenèvre

The Dora Riparia (Italian: [ˈdɔːra riˈpaːrja]; Piedmontese: Dòira Rivaira; French: Doire Ripaire or Doire; Latin: Duria minor) is an alpine river, a left-bank tributary of the Po. It is 125 kilometres (78 mi) long (of which 5 km is in France), with a 1,231 square kilometres (475 sq mi) drainage basin. It originates in the Cottian Alps, close to the Col de Montgenèvre in France, where it is called the Piccola Dora. Its name becomes the Dora Riparia after the confluence with the Ripa in the Argentera Valley and the Thuras de Bousson close to Cesana Torinese.

Further down the valley, in Oulx, the river grows thanks to its main upper tributary, the Dora di Bardonecchia, and before Susa is augmented by the Galambra and Cenischia. After Susa, it only receives minor tributaries: from the left, Gravio by Condove, Sessi by Caprie, and Messa by Almese, from the right Scaglione by Meana and Gravio by Villar Focchiardo. It runs through the Susa Valley, and after having crossed part of the plain of the Po and the territories of the comunes of Avigliana, Alpignano, Pianezza and Collegno, joins the Po at Turin. It is considered a "stream" (torrente) until Susa, and a river (fiume) to Turin.