The studies undertaken at the Laboratory for Research of Historical Monuments aim at getting a better knowledge of the environment of ornamented caves and a better understanding of their climatic, geological, and hydrogeological parameters. Two directions are defined: the one, toward theoretical studies and, to cite the environment of the Font de Gaume cave, the general conditions of conservation of the prehistoric paintings of the Tete du Lion cave; the other, toward interventions and maintenance problems such as the elimination of graffitti. The Lascaux cave is a concrete example of a synthesis of those two directions. In this case, theoretical studies and interventions have taken place since 1963, when the cave was closed to the public and research started on the conservation of this monument.