This was once a yellow limestone extraction site characteristic of the southern Beaujolais. It supplied the region in construction material for centuries. As the only visitable quarry in the Rhône area, it is also a natural area of ecological interest.
This limestone formed from 175 million years ago, a time when Beaujolais region was covered by ocean, was a good building material. The extraction of rocks has, over the years, created shelters for bats, and the argilo-limestone subsoil is covered by a great diversity of plants. There more than 300 species in total, from the common deciduous trees to the rarer orchids.
The site stands clear of all this vegetation and offers stunning views over the Azergues valley, the Tarare hills, and some of the Lyonnais hills.
The Glay quarry makes for an interesting visit, with explanatory signs dotted along a path and guided tours provided by the "Carrières de Glay" association to help you find out all about the history of the site.
Pour que le site puisse rester ouvert au public, il est demandé à chacun de respecter les lieux (feu interdit, ne pas laisser de détritus,...) et d'être chaussé pour la randonnée et d'avoir une bonne condition physique pour faire le "sentier du front de taille" (circuit rouge) : passages difficiles et marches hautes, parfois glissantes. Merci de votre compréhension.