The origin of the Castellana Caves

The history of the Grave of the Castellana Caves begins in the late Cretaceous period (XNUMX–XNUMX million years ago), when Apulia was submerged by an ancient sea inhabited by vast colonies of mollusks and marine plants.
The history of the Grave in the Castellana Caves began in the Late Cretaceous period, between XNUMX and XNUMX million years ago, when the region of Apulia was submerged by an ancient sea teeming with vast colonies of molluscs and marine plants. For millions of years, generation after generation of these life forms succeeded one another. As they died, their empty shells and carcasses accumulated on the seabed, forming an enormous deposit of mud and sand. This deposit slowly but continuously grew and compressed to form a layer of limestone several kilometres thick. Starting sixty-five million years ago, the region's current appearance was formed by the gradual uplift of the land, which caused extensive fractures to form in the exposed limestone due to its rigidity. Eluvial water from heavy rainfall percolated into the subsoil and formed an extensive underground aquifer. This gradually dissolved the limestone and widened the fractures, which eventually joined together due to the collapse of the rock between them. Thus, small channels gradually expanded into ever-wider spaces. Where the fractures intersected in large numbers, as was more pronounced in the Grave than at any other point in the Castellano karst system, there were extensive and repeated collapses. These expanded ever higher, reducing the thickness of the rock separating the cavity from the outside over time. Eventually, the remaining layer collapsed, allowing the first ray of light to reach the interior of the Grave.