Aven d'Orgnac

Robert de Joly explored the aven in 1935 by descending the natural shaft that gives the cave its name, and what he found were chambers on a scale unusual even for the region, the first of them around two hundred and fifty metres long. The formations here have an odd character: many are squat, wide stalagmites built up in stacked discs, sometimes called pile-of-plates, formed where drips fall a long way and splash. Others are thin and conical. Visitors descend around seven hundred steps in and return by lift. A museum on the surface covers regional prehistory, and the site carries the Grand Site de France label.

What you actually see

• The stacked-disc stalagmites - squat formations built by long-falling drips.
• The great chambers - halls hundreds of metres long underground.
• The natural shaft - the sinkhole the first explorer descended.
• The prehistory museum - regional archaeology on the surface.

When to go

Year-round; the cave stays around twelve degrees whatever the weather, which makes it a good hot-day option. Closed for parts of winter. Summer visits should be booked.

Honest expectations

The descent is around seven hundred steps and the return is by lift, so the route is one-way and not accessible for limited mobility. It is cold and damp inside. Tours are guided at fixed times.

Nearby

The Ardeche gorges lie north; Chauvet 2 is northwest.