The Réserve Géologique de Haute-Provence covers 2,000 square kilometres of mountain country north of Digne and is one of the largest protected geological zones in Europe. The landscape preserves 300 million years of geological history in exposed rock faces, fossil beds, and formations created by the collision of tectonic plates that built the Alps.
For walkers, the reserve offers some of the finest empty mountain country in southern France. Marked trails lead through the ichthyosaur site (marine reptiles from the Triassic period), the ammonite hillside near the village of Barles, and the canyon country of the Clue de Barles. The town of Barles, 25 km north of Digne, is the main gateway for the northern sections. Maps and information are available at the Musée Gassendi, which also serves as the reserve's information centre.