The Montgrí is a massif of carbonate rock which arose at the same time that the Pyrenees formed. The carbonate rock gives rise to a karstic landscape with numerous interesting geological formations. Limestone pavements are one of these formations. They appear on rocks which are on the surface. Rainwater is naturally slightly acidic and dissolves carbonate rock, forming small channels where the water runs or small cavities where water accumulates. These channels gradually erode over time, creating these very interesting sharp stones, around which it is important to be careful to avoid hurting yourself.