In the winter landscape on the Aubrac plateau, snow covers the backdrop with a white coat. There are also many stalactites, concretions formed from drops of water that bead from the ceilings of galleries and caves. Their common name comes from the Greek stalaktos: 'which drips'. Calcareous stalactites are formed when rainwater passes very slowly through the ground. It takes on carbon dioxide and becomes very acidic. In winter, ice stalactites also form along gutters and trees.