Can we see on the Arcy site the different geological layers that have been superimposed over time? Arcy is typical of the Karstic section, it is possible to identify different geological layers by walking on the path that runs along the Cure. What is the main characteristic of the Arcy Massif that explains so many caves? The nature of its clay-limestone massif formed nearly 150 million years ago. What is the difference between stalagmites and stalactites, how do they develop? We explain the concretions during the visits so here we keep the mystery!