Lascaux (Lascaux Caves) is the setting of a complex of caves in southwestern France famous for its Paleolithic cave paintings. The original caves are located near the village of Montignac, in the department of Dordogne. They contain some of the best-known Upper Paleolithic art. These paintings are estimated to be 17,300 years old. They primarily consist of images of large animals, most of which are known from fossil evidence to have lived in the area at the time. In 1979, Lascaux was added to the UNESCO World Heritage Sites list along with other prehistoric sites in the Vézère valley.

On September 12, 1940, the entrance to Lascaux Cave was discovered by 18-year-old Marcel Ravidat. Ravidat returned to the scene with three friends, Jacques Marsal, Georges Agnel, and Simon Coencas, and entered the cave via a long shaft. The teenagers discovered that the cave walls were covered with depictions of animals. The cave complex was opened to the public in 1948. By 1955, the carbon dioxide, heat, humidity, and other contaminants produced by 1,200 visitors per day had visibly damaged the paintings and introduced lichen on the walls. The cave was closed to the public in 1963 to preserve the art. After the cave was closed, the paintings were restored to their original state and were monitored daily. Rooms in the cave include the Hall of the Bulls, the Passageway, the Shaft, the Nave, the Apse, and the Chamber of Felines. Lascaux II, a replica of the Great Hall of the Bulls and the Painted Gallery located 200 meters away from the original, was opened in 1983, so that visitors may view the painted scenes without harming the originals. Reproductions of other Lascaux artwork can be seen at the Centre of Prehistoric Art at Le Thot, France.

Since 1998, the cave has been beset with a fungus, variously blamed on a new air conditioning system that was installed in the caves, the use of high-powered lights and the presence of too many visitors. As of 2008, the cave contained black mold which scientists were and still are trying to keep away from the paintings. In January 2008, authorities closed the cave for three months even to scientists and preservationists. A single individual was allowed to enter the cave for 20 minutes once a week to monitor climatic conditions. Now only a few scientific experts are allowed to work inside the cave and just for a few days a month but the efforts to remove the mold have taken a toll, leaving dark patches and damaging the pigments on the walls.