Le Tertre Gris

Starting from Poligné, a signposted-circuit through a beautifully wooded slope gives a superb panorama over the Semnon, spanned by an 18th Century shale bridge with 3 arches. This site's white sandstone mound and the black clay rocks, rich in organic matter, are of geological interest and it is also used as an educational support, receiving geological excursions. The legend which says that the Poligné Volcano is still in activity, has been accredited to the thick black smoke which came out...