A deep, steep-sided canyon at the southern part of France's Massif Central mountain range, at the edge of the Causse du Larzac. The "cirque" is a deep circular basin that was carved out by the meandering Vis river that created an oxbow at that spot. The oxbow eroded through at the neck to create an oxbow lake. When the lake dried up, what remained was the circular basin with arable land around a small center hill.
The Upper Roya Valley begins at the Col de Tende (1871 m) on the French-Italian border. It runs south about 35 km to Breil-sur-Roya and then another 8 km to where it crosses back into Italy. (The Lower Roya Valley flows into the Mediterranean at Ventimiglia.)