>>1137192There are quite a lot of them here
The southern end of the Massif Central range near where I took the pictures is mostly limestone soil. There are 7 major limestone plateaux around here, called "causses", the most famous being the Larzac and the causse Méjean
They feature a fuck ton of caves, tunnels, underground rivers... Some have become tourist attractions for their beautiful mineral formations (like the Aven Armand) or for their pre-historical paintings/carvings, but there are also hundreds of minor caves where no one ever set foot that are great for camping and outdoor activities. There are also great river gorges that cut deeply through those plateaux
If you are interested you can see some beautiful footage here
https://www.youtube.com/watch?v=SS1YJIoMdMgIt's a French TV program but the pictures and videos need no translation
