Grotte de Gournier

A 40-metre lake, together with the traverse that follows it, is the only real difficulty of this introductory trip; it is 6 metres deep. After the traverse, one steps into a vast fossil gallery, with a water inflow on the side, the origin of the calcite flow that had to be bypassed from above (alias “La Méduse”). One then progresses through an ascending gallery, but subject to roller-coaster-like altimetric fluctuations; after a first low point that sumps in flood, the gallery takes on its effective dimensions, which it will keep for a good part of its existence. We pass chimneys, access to the réseau des Deux Jean and to the réseau Inattendu. At 800 metres from the entrance, one arrives in the salle des Fontaines, a superb decorated chamber, with a very original active feature, since it has created a symmetrical fountain, bordered by immense gours. Further on, the gallery becomes meandering and very jagged. One emerges into a very vast fossil gallery (20m x 20m): the galerie du Chaos, at the end of which le bivouac des Dijonnais is set up on the heights; coming back down on the left one finds the river and the start of the Aquagalerie, a fabulous water street. The cavity continues, to be described later.

a powerful headlamp is recommended, allowing one to discover the wonders of this gallery, both in decoration and in shapes, colours or starts. The salle des Fontaines is a superb decorated chamber, with a very original active feature, since it has created a symmetrical fountain, bordered by immense gours. a fossil gallery on the left contains a few muddy pools and numerous concretions.

The difficulty of progressing in the river depends greatly on the water level, crossing gours of varying depth and small steps. The first low point of the ascending gallery sumps in flood. The siphon Jérôme is no longer a sump: one can notice the shot marks at the entrance of the narrow passage that allowed its level to be lowered. At 5255m and +405m of elevation gain from the entrance there is a 5m cascade (alias P5 or terminus SCL 75).

From the entrance to the rivière souterraine (underground river) (entrances 1 and 2)

General (simplified) survey: https://speleo-canyon.com/uploads/parcours/images/66427609276fa_Gournier.jpg

Cross this body of water 6 metres deep on the right bank (that is, on the left when entering), to reach a spacious stalagmitic landing. Climb 5 metres directly above it, to rig the traverse (bolts in place). An ascent between blocks on the left side allows one to reach the tributary of point 900. It is in this sector, in the centre of the gallery, that one must find entrance 1 to the river; this can make a first goal for a walk (elevation approx. +55), allow 1h30 with a group of non-cavers who are good walkers. The first access of this entrance 1 is exposed, and equipped with a cordelette to install a rope; it is preferable instead to take the left just next to it and pass between the blocks to descend without needing equipment.

Instead of descending into the river here, it is possible to continue to entrance 2: continue along the fossil gallery, and via a traverse on the left side, one passes a portal of concretions: the “Cascade Rouge”. A few tens of metres of tedious going follow, before emerging onto a balcony at the Salle à Manger, a vast funnel whose bottom constitutes the second access to the river (the passage is on the right side of the gallery, in a depression and marked with a carbide arrow with the figure “2”). Allow 2 hours for this part with a group of 8 non-caver good walkers.

From the rivière souterraine (underground river) to the siphon Jérôme (ex-siphon 1)

This description disregards the entrance lake and the great fossil gallery in order to describe the route in the river from entrance 2. Progress is sometimes made with the help of the via ferrata rungs in place for the rare athletic passages. The first notable obstacle is the 5m cascade (C5), which is climbed precisely via the rungs (possibility of installing a rope if needed), and continues as a fixed handrail (in 2026). Further on, a step is already fixed-equipped (in 2026) and allows one to gain a little height. The most notable obstacle is then the 12-metre cascade (C12), also equipped with via ferrata rungs on the right and a fixed rope (in 2026) for safety.

Continue in the river until reaching a sort of dead end. One must leave the river to climb the fixed rope on the left, from where a little water may flow. One arrives in a narrow forced conduit; one must be careful because what follows is a little confusing. Take a first left in the mini-meander, then quickly right through a squeeze. One must then climb a chaos of blocks following the cairns, until coming upon ropes. What follows is a 30m ascent, very broken up, in via cordata mode (one thus climbs the P40 of the Grande Barrière by bypassing it). At the top, one rejoins the river at the foot of a large cascade: welcome to the salle Chevalier. In general, this is an honourable terminus for a good walk of 6-8 heures in total for a group of cavers.

It is possible to push on to the siphon Jérôme, by means of the complete rope ascent equipment; the equipment and the state of the ropes are more approximate (in 2026). In that case, climb the fixed rope beside the cascade. A change of atmosphere to arrive in a somewhat muddy gallery shaped like the ace of spades. Continue to emerge onto a large chamber on the left. There follow an ascent of a small step equipped with a rope and an old caving ladder, and several fractioned pits. One soon finds the water again and beautiful cascades. Descent of a P10 and ascent of a P10 with an exit onto a fairly sporting handrail! One passes through more aquatic sections to climb a cascade. The passage narrows to arrive at the siphon Jérôme. Le retour (the return) really resembles a canyon, there is even a 3-metre jump into a pool (mind the water level all the same...) and descents in cascades.

From the siphon Jérôme to the Aquagalerie

This description disregards everything from the start up to siphon 1. Swim across the ex-siphon (about 35m) to the fixed rope in the middle of the lake and climb it (it is advisable to prepare one's rope ascent equipment before starting to swim!). About 650m further on, fixed ropes allow one to climb up to the réseau de l'affluent des Lyonnais (otherwise 25m further on one comes up against the siphon des Lyonnais, alias siphon 2). One continues to a fossil gallery on the left. After a few low passages and two small pits (fixed in 2026), one descends having bypassed the sump. One finds the river again and its canyon profile, interspersed with cascades and pools, which one follows for a good while (galerie des deux plongeurs and galerie de la Varappe).

Note all along the route numerous fossils, including sorts of shells 20cm long. There is a very beautiful fossil when swimming through the active passage on the left, 3 metres after entering the water at about 1 metre 20 above the water level.