The Île-de-France (Isle of France) is the region of the capital Paris and also called the Région parisienne (Paris Region). It is located in a basin filled with Mesozoic sedimentary rocks. While there are thick layers of limestone underground, the relief does not allow underground drainage, and so there is no karst and no caves. But the limestone was quarried underground for centuries to erect the buildings on the surface. The undergroing sites in this region are all artificial, and most of them actually use the abandoned limestone quarries.