Châtelus

Upstream from Pont en Royans, the Bourne valley which opens out between the Coulmes Massif and the
Allier
plateau, forms a vast transverse valley where are installed, opposite each other, the villages of Choranche and Châtelus. This last hangs on at the foot of the Grande Cournouse and Bournillon rocks. In boundaries of the village, rises a round neckline dug in arc of a circle in the limestone mass of the
Allier
plateau : the cirque of Bournillon.