Goule de Foussoubie

Goule de Foussoubie is a swallow-hole where a surface stream vanishes into the limestone plateau above the Gorges de l'Ardèche, in the commune of Labastide-de-Virac. In the local dialect a "goule" is exactly that: the mouth through which running water disappears underground, and here it swallows a small brook known as la Planche as it meets the Urgonian limestone of the massif.

What is actually down there?

Below the sinkhole stretches one of the region's largest karst systems: more than 23 km of surveyed galleries with a vertical range of about 138 m, running beneath the communes of Vagnas, Labastide-de-Virac and Salavas. Rainwater collected across a few square kilometres of plateau sinks in at the goule, travels underground for several kilometres, and re-emerges into the Ardèche river close to the Pont d'Arc, the natural rock arch that has become the symbol of the gorges. Along the way, cavers have mapped roughly a dozen siphons — fully flooded passages — several of which have been dived through to reach further sections of the network.

Exploration and a cautionary chapter

Serious study of Foussoubie began with pioneering French speleologist Robert de Joly, and from 1959 onward caving clubs led by Jacques Noël pushed the survey much further. The system has also shown how dangerous it can be: in June 1963, a sudden storm sent floodwater surging through the passages and two cavers lost their lives inside. The episode is still cited locally as the reason independent, unguided descents are strongly discouraged — the cave can flood within minutes of rain falling on the plateau above.

Can visitors go inside?

Yes, but only as part of an organised trip. Caving operators based around Vallon-Pont-d'Arc run a guided "through-trip" starting at the nearby Event de Cordier entrance and exiting at Foussoubie. It's a half-day outing, roughly 2.5 to 3 hours, opening with a tight squeeze and an initial abseil of around 30 m, continuing through spacious chambers and narrower meanders, and finishing with a wet stretch featuring several natural pools before a dramatic funnel-shaped final pitch about 20 m deep. Cave temperature stays close to 13°C year-round, so groups are issued wetsuits by the guiding company.

Frequently asked questions

Where exactly is Goule de Foussoubie?

In the commune of Labastide-de-Virac, Ardèche, on the plateau edge bordering the Gorges de l'Ardèche, a short drive from Vallon-Pont-d'Arc and the Pont d'Arc.

Can you explore it on your own?

It isn't advisable. The cave is an active swallow-hole that responds fast to rainfall, with roped drops and flooded passages — access in practice means joining a guided group with a certified instructor.

What's the minimum age for the guided trip?

Commercial "Cordier to Foussoubie" traverses are typically open from around age 12, run in small groups with professional supervision.

How long does the visit take?

The standard underground crossing takes about 2.5 to 3 hours, combining rope descents, tight passages and a final aquatic section.

Why is it called a "goule"?

It's the regional term for a swallow-hole — the point where a surface stream sinks into a limestone massif and continues its course as an underground river.