Cévennes International Dark Sky Reserve: The Mont Aigoual

Required Activities

• Climb to the Mont Aigoual observatory, a fortress of granite with a crenellated tower built between 1887 and 1894, go up to the army's orientation table on top of the tower at 1,571 m and use it to name what you can see, then work through the weather exhibition Météo-France and the local communes run inside the building that housed the last resident meteorologists in France

• Wait out the cloud for a clear night — the Aigoual is fogbound on 240 days of an average year — then photograph the Milky Way from the summit plateau inside Europe's largest dark sky reserve, and turn round to shoot the observatory tower against the stars with no light source of your own

• Walk down the south-east flank to the Hort de Dieu, the arboretum Georges Fabre and the botanist Charles Flahault planted in 1902 with 773 trees and over 1,200 plants at 1,300 m to find out what would survive up here; pick out the survivors — Vancouver fir, larch, hooked pine, Corsican pine — knowing only half the species they tried are still standing, and find the 1936 stele to the botanists who worked on it

• At Camprieu, walk the Bonheur down its five-kilometre valley to the points where it disappears into the limestone, then take the guided kilometre through the Abîme de Bramabiau to the 70 m fissure the river bursts out of, and listen at the 10 m fall that gives the place its Occitan name, the bellowing bull — Martel's 1,300 m traverse of this cave on 28 June 1888 is treated as the birth of caving