La Verna cave

660 metres (2,170 ft) of mined tunnel leads into the Salle de la Verna, the largest chamber in a show cave in the world.

The chamber was named after the Lyon scouts, La Verna Troop, who helped in the attempted rescue of Marcel Loubens who died following a fall during the 1952 explorations.

[5][6][7] Explorations still continue in this and in other systems within the extensive Pierre-Saint-Martin karst area where 13 underground rivers and a total of 288 kilometres (179 mi) of passages, chambers and shafts have been mapped.

[8][9] Most of the Gouffre de la Pierre-Saint-Martin is formed by dissolution in Cretaceous limestones, and the main river reaches a base level where it flows over insoluble schists of the Paleozoic basement rocks.

Since the opening of la Verna to visitors, in 2010, a team of researchers of the French national museum of natural history, under the leadership of Professor Arnaud Faille, closely follows their evolution.

Platform overlooking Salle de la Verna
Waterfall in Salle de la Verna
Near the Gouffre des Partages
Aphaenops ochsi cabidochei in the salle de La Verna
Expédition of 1952 to the gouffre de la Pierre Saint-Martin.