The Cave Paintings at Lascaux
Sometime around 15,000 B.C. humans make these drawings, on the wall of a cavern in what is now southwestern France. Though it is impossible to know for sure, they were probably used as part of an animistic ritual. Along with the many other paintings discovered in caves in Europe from that period, they are a potent reminder of the moment in our history when tools and intellect first meshed.

• To learn more about TIME History's Greatest Events, click here