Lascaux

The cave complex was opened to the public on 14 July 1948, and initial archaeological investigations began a year later, focusing on the Shaft. By 1955, carbon dioxide, heat, humidity, and other contaminants produced by 1,200 visitors per day had visibly damaged the paintings. As air condition deteriorated, fungi and lichen increasingly infested the walls. Consequently, the cave was closed to the public in 1963, the paintings were restored to their original state, and a monitoring system on a daily basis was introduced.