A dog looking for its owner led four teenagers into Lascaux, and the paintings they found are still dated to well over ten thousand years before any written language existed.
Found by following a dog
In September 1940, four local teenagers, most often named as Marcel Ravidat and his companions, followed Ravidat's dog into a hole exposed by a fallen tree near Montignac, and discovered the painted cave system by climbing down into it with a makeshift lamp, an entirely accidental find that predates any organised archaeological search of the hillside.
What is on the walls
The cave's most famous chamber, the Hall of the Bulls, depicts large aurochs, horses and deer in mineral pigment, painted with a scale and confidence that surprised early researchers unused to attributing such technical skill to Palaeolithic artists. A separate, more obscure scene deep in a shaft depicts a bird-headed human figure apparently falling before a wounded bison, one of the few explicitly narrative or human scenes in the entire cave, and one of the most debated in terms of what it depicts.
A conservation history of one problem replacing another
As this entry's companion article covers, opening the cave to the public in 1948 introduced algae growth from visitor breath and lighting, and each subsequent technical fix, closing the cave, adjusting climate control, introducing new treatments, tended to produce its own new form of damage rather than a clean resolution, a cycle that eventually led to the cave's permanent closure to the public.