IT IS a cave so closely guarded that only three people know the code to the half-tonne reinforced door that seals its entrance, where cameras keep watch 24 hours a day.
But we were given a rare chance to step through this gateway into prehistory and into the depths of the Grotte Chauvet in southern France — home to the earliest known figurative drawings and now a World Heritage site.
For tens of thousands of years, time stopped in the cave nestled deep in a limestone cliff that hangs over the lush, meandering Ardeche River, until it was discovered in 1994 by a group of cave experts.
To reach the site, which is closed to the public, the lucky few allowed access must hike up a path that our Cro-Magnon ancestors once used, not far from a natural stone bridge that straddles an abandoned part of the river.
Some 36,000 years ago — the age of the cave paintings — tall Scots pines lorded over the cliff in a climate equivalent to that of present-day southern Norway.
After arriving at the entrance in sweltering heat, descending into the Palaeolithic den brings a sharp drop in temperature and almost 100 per cent humidity.
Marie Bardisa, the curator of the site, types in the code to the fortified door and it slowly swings open.
Visitors must put on white overalls and special shoes to avoid polluting the environment, as well as a helmet and harness.
“The idea is to keep the cave in the same state of containment as when it was discovered,” Bardisa says.
“We watch over the atmospheric balance, we monitor the potential proliferation of algae, mushrooms or bacteria.”
Now begins the travel through time. After crawling through a narrow tunnel, visitors reach man-made stairs. At the bottom, the silent, cool cave opens up.
Nearly everything has been left as it was when Jean-Marie Chauvet, Christian Hillaire and Eliette Brunel stumbled across the grotto on December 18, 1994.
Crystals on huge limestone formations sparkle in the lamp light. Bones coated with clay and calcite litter the cave, proving that bears lived here before and after humans passed through. The skull of an Alpine ibex, a species of wild goat, smiles through immaculate teeth.
Visitors are not allowed to walk freely through the site but must stick to a tiny walkway that makes movement difficult.
Paintings of hands — made using a technique of blowing red ochre pigment onto the wall around the hand — appear out of the dark as a guide shines a powerful lamp onto the wall.
Further away, an image of a red bear with a spotty face stands over the only known drawing of a panther among all cave paintings from the Palaeolithic era.
“Chauvet alone houses 75 per cent of big cats and 60 per cent of rhinoceroses” known to have been drawn during the period, says Charles Chauveau, the site’s deputy curator.