The Petite Cuisance tuff waterfalls near Les Planches-près-Arbois, Jura. The waterfall is fed by an underground river, the Dard. © Masterfile / Martin Ruegner
BRGM - 3 avenue Claude-Guillemin - BP 36009 45060 Orléans Cedex 2 - France Tel.: +33 (0)2 38 64 34 34