Archiane, Forest managed biological reserve in the Vercors highlands, Drôme department, France.

Archiane biological reserve spans 727.95 hectares of communal forest in Châtillon-en-Diois, enclosed by towering 400-meter limestone cliffs that form a natural amphitheater at the southern edge of the Vercors massif, dominated by Mount Glandasse.

Established on March 8, 2000, this reserve protects geological formations dating back over 120 million years to the Cretaceous period, with limestone escarpments that have been shaped by millennia of erosion and are listed in the national geological heritage inventory.

The reserve lies on the old transhumance route between the Diois valley and the Vercors plateaus, where flocks still move up to summer pastures. The hamlet of Archiane, at the reserve entrance, keeps stone sheepfolds and terraced fields that show how grazing shaped the slopes. Picodon, the small goat cheese of the Drôme, is still made on surrounding farms.

Access to the reserve follows a discovery trail starting from Archiane hamlet, with marked paths allowing natural habitat observation while adhering to regulations that restrict logging, hunting, and motorized vehicles to protect sensitive environments.

The Griffon Vulture colony here grew from birds released in the 1990s, and the cliffs now hold about 80 breeding pairs. Among the six nationally protected plants are the Lady's Slipper orchid and the Wild Tulip, both easily overlooked by walkers on the reserve paths.