Creux Billard

Creux Billard is a pit cave near Nans-sous-Sainte-Anne featuring a circular collapse shaft roughly 60 meters (196 feet) across and 90 meters (295 feet) deep. A lake at the bottom connects to underground galleries that extend into the earth.

In 1889, a tragic incident occurred when Miss Lachelier drowned in the chasm, and her body was recovered eight days later downstream. This discovery proved the water connection between the shaft and the Lison spring.

The site earned protected status together with the Lison spring and Sarrazine cave because of its geological and natural importance. This classification reflects recognition of the area as a significant natural site.

The observation platform is reachable via a hiking trail starting from the Lison spring cascade, with stairs for easier access through the woodland path. The site is reasonably accessible if you use the provided steps and allow time for the walk.

During high water periods, two waterfalls flow simultaneously from the Château-Renaud stream, one emerging from the surface and another from a cave opening visible in the north wall. This rare sight reveals how water circulates through the underground system.