Couloir Saone et Rhone, 1923Couloir Saone et Rhone, 1923. Scale 1: 1,600,000 approx. Colour print, 44x42cm. Flat with single central fold and binding fin on reverse. Geological map of the corridor of the Rhone and Saone river valleys and relief maps of Lyon and Valence regions, scale 1: 120,000 approx. The geological map occupies the left half of the page and is not affected by the fold. In very good condition.