This is Europe's largest geological reserve: 1900sq km, encompassing 47 districts. Rocks, fossils and landscapes are a testimony to 300 million years of history of the earth. The reserve is divided into twenty protected sites that can be accessed from Digne, Castellane or Sisteron; visits of one day or one week, on foot or horseback, with a geologist guide are all possible. A prerequisite is a visit to the St Benedict's Promenade-Museum which is responsible for the reserve.