Grotte de la Draye Blanche, Natural limestone cave in La Chapelle-en-Vercors, France.

Grotte de la Draye Blanche is a cave in La Chapelle-en-Vercors whose main chamber measures about 100 metres by 30. Its walls carry mineral curtains shaped by seeping water, large draped stalactites and ochre-tinted rock, and the cavity is 4.7 million years old. A 16-metre shaft, a gallery and the chamber were found in 1918; a tunnel pierced in 1990 opposite the natural entrance now serves visitors.

In 1918 Fabien Rey, a hermit known as "Marseille" who lived with about thirty dogs, found the cave while searching for his dog Fleury, fallen into a 16 m deep scialet. The gallery and lighting were completed in August 1970 before the discoverer, then in his eighties. In 1990 a tunnel was bored opposite the natural entrance, uncovering a filled shaft with 15,000 bones of 45 species.

The cave has had several names: first Grotte Fleury, after the dog Fabien Rey was chasing when he found it in 1918, then Grotte de la Draye Blanche, and today Grotte de la Percée Blanche. The dog fell into a 16-metre scialet, a local term for a karst shaft, and Rey climbed down to rescue it. Guided tours last about 45 minutes.

Visits are only possible with a guide and last about 45 minutes; the tour is commented and covers the fossil studies. The entrance lies beside the RD 178 between La Chapelle-en-Vercors and Vassieux-en-Vercors, near the hamlet of Les Croix, and no railway station or bus stop is nearby. The 1990 tunnel opposite the natural entrance now serves visitors.

When workers bored the 1990 access tunnel opposite the natural entrance, they broke into a shaft blocked at the surface by rubble. This natural trap held over 15,000 bones of 45 species, from shrew to cave bear, bison, wolf and eagle. The guided tour explains what these fossils reveal about the animals that lived near the cave.