In 1990, in the gorges of Aveyron, a teenager passionate about speleology, Bruno Kowalczewski, discovered a cave near the village of Bruniquel. After having dug for three years to make a passage from a tiny hole, it emerges 350 meters from the entrance, into a spacious cavity containing an archaeological treasure. On the ground, hundreds of shattered stalagmites were arranged in circles by Neanderthals, as evidenced by a carbon-14 dating to at least 47,000 years ago. What significance do these limestone rings have? From when do they date precisely? For fear of damaging the remains, excavations were stopped at the end of the 1990s, leaving these questions unanswered. They resume today.