As I descend a footpath through subterranean gloom, limestone walls tower 40 feet and plunge into a chasm. Gleaming stalactites dangle from the ceiling. After several twists and turns, I reach a cul-de-sac. As I shine my iPhone flashlight on the walls, out of the darkness emerge drawings in charcoal and red ocher of woolly rhinos, mammoths and other mammals that began to die out during the Pleistocene era, about 10,000 years ago.
It feels, and even smells, like a journey into a deep hole in the earth. But this excursion is actually taking place in a giant concrete shed set in the pine-forested hills of the Ardèche Gorge in southern France. The rock walls are stone-colored mortar molded over metal scaffolding; the stalactites were fashioned from plastic and paint in a Paris atelier. Some of the wall paintings are the work of my guide, Alain Dalis, and the team of fellow artists at his studio, Arc et Os, in Montignac, north of Toulouse.