The collapse of the northern section of Combalou mountain in Aveyron created an underground maze of caverns, "fleurines", whose humidity and temperature are constant. This unique, natural ventilation is at the origin of the transformation of Roquefort cheese, thanks to penicillium roqueforti, which gives the famous cheese its blue-green marbling. To find out more about this universe and the manufacture of this emblematic cheese, several cheese cellars are open to the public: Papillon, Société, etc.