In the 1960s, the Spéléo Club de la Seine found the way on, but were eventually stopped by a sump at a height of +270 metres (890 ft).

In November 1976, while to pass the obstacle, three speleologists from the Rhone region, Michel Schmidt, Roland Chenevier and Daniel Trouilleux, were swept away by a flood.

[5] In August 1996, a cave diver, Frédéric Poggia, dived the sump l'affluent des Parisiens, discovering 1,200 metres (3,900 ft) of passages.

[6] Speleologists have been digging sinkholes above the end of the cave for several years, hoping to reach the underlying passages.

After the Salle des Burgondes, the gallery becomes broader, and then the passages become high and narrow, often requiring travsersing, to close down at +680 m (2,230 ft).

[9] The fossil gallery was probably formed in the Pliocene in a subtropical climate, 3–4 million years ago.