Interesting landscapes are not only found on the Earth’s surface, but also in the depths of the Earth. We are speaking of underground cavities, caves, that are very important for various aspects. All the changes that take place around the cave, such as tectonic movements, climatic changes, changes in the topography, cause changes inside the karst systems, that tend to find a new balance with the new situation. Therefore, caves are not characterized by stable features, that do not change in time and space; it must always be borne in mind that they were formed in topographic and climatic situations that were greatly different from the current situation. The study of the sediments that are carried inside the caves, with their characteristics, their composition, their contents in fossils, enables us to reconstruct the variations in the environment and in the climate on the Earth’s surface. Karst aquifers account for a very important source of water in a large number of regions of the Earth: in fact karst areas are, by nature, without water on the surface and all the water circulation takes place underground. However these resources are very delicate to use and to protect. In fact karst aquifers, due to some of their characteristics, are particularly vulnerable to pollution and excessive exploitation.