Saint Antoine Supérieure (Entrée de la source)

La Source St Antoine has a lower entrance and an upper entrance. The lower entrance leads to a masonry-lined gallery. A pit about fifteen meters deep controls access to the exit pool of S2 and the entry pool of S3. The entry pool of S3 is vast and allows several divers to gear up comfortably beside a pumping pipe that plunges into the crystalline water of the sump. The entry pool of sump 4 is small (2 m by 2 m). The sump emerges after 80 meters into a very large chamber made of jumbled rocks. Sump 4 plunges to -10 m over about thirty meters before reaching a very large chamber. At the entrance to the chamber, a tunnel branches off immediately to the left down to -20 m. The passage continues for a few tens of meters before rising gently. The ascent toward a small bell (50 cm) at 200 meters from the entrance follows a gentle slope in a setting of sculpted rocks, alternating passages and fine volumes. Past the owl's eye that leads to the high point, the gallery descends to -50 m, still in passages of sculpted rock, then rises abruptly to -42. It then descends to the entrance of a fault at -91 m. The gallery then resumes its comfortable shape and continues descending at 45 degrees.

The highly jagged rock with yellow reflections, characteristic of St Antoine, coexists with large surfaces of clay. The gallery passes beneath a lace of rock in which the water has sculpted the shape of a dragon's head, the guardian of S4.

It is necessary to walk about thirty meters in 50 centimeters of water to reach the entrance of sump 1. This sump runs about fifty meters, at the end of which one surfaces before plunging again into sump 2 for about forty meters, all of this at less than 10 m of depth. One then arrives in a magnificent pool that is itself directly accessible from the upper entrance. The sump descends along a 45-degree slope to a depth of 19 meters, in the middle of which is a pump unused for years. A horizontal section of about ten meters leads to the line of a shaft that rises almost vertically to the surface. The large surfaces of clay need only to disturb the absolutely crystalline water of the gallery.

Development work (zip line, unloading platform, …) was carried out by Plongeesout to facilitate the transport of equipment. It is then necessary to remove one's gear to cross the 80 meters of intersump that lead to sump 4. One must then slip into the fault a little before the end of the passage (Bollanz had descended to the end of the passage) and let oneself slide gently down to -110.