Morning 11°c
Afternoon 17°c

Geological path

The Platé Mountain owes its name to its vast stretches of gently sloping limestone, such as the Platé Desert or the Sales bowl.

Numerous fossils bearing witness as to how the different environments evolved over the course of its 170 million year history: from deep seas to reef environment, from lagoons to inland waters.


The mountain is home to one of the biggest high altitude karstic networks in the Alps. The lapies or limestone pavements are indicative of these networks with their indented and engraved surfaces whose varied forms depend on the limestone’s texture, faults, gradient…
This erosion is the result of water dissolving the limestone. Water, containing carbon dioxide, reacts with the calcium carbonate, thereby making it soluble.
The insoluble elements contained within the limestone are deposited in the cracks of the lapies, forming a soil base where plants can take hold in the lee of the wind.
As for the dissolved limestone, favourable changes in temperature or pressure conditions cause it to precipitate. This precipitate takes the form of stalactites, stalagmites or encrusted sources.

The name’s origin

Rain water and melting snow have continuously sculpted these vast expanses of limestone since the end of the ice ages.
Taking advantage of the rocks’ weakness, water seeps into the cracks and faults, thereby creating caves and chasms deep down in the rock.
The “Platé Desert” is therefore aptly named. There is no water flowing on the surface. Only a handful of bodies of water can be seen on the surface, such as the “Laouchets de Platé”. Water flows underground, only emerging from the edge of the mountain when it reaches faulted or impermeable rock.
In the absence of filtration, the slightest surface pollution leads to a deterioration of its quality.


Many fossils from the Early Cretaceous Period bear witness to a warm marine reef environment and can be spotted on the vast flat surfaces where the layers are exposed: Urchins; Rudists (bivalve molluscs); Nerinaea and Cerithiids (Gastropods); shellfish burrows and even vertebrate bones to the trained eye.


Book your skipass