Sommet Bucher on mountain bike

Since the beginning of the Quaternary (2.58 million years ago) glacial periods have shaped the landscape. In a progression phase, the glaciers move forward and dig a hole in the ground. Sometimes they meet harder rocks which they "bypass". At their moving, they leave behind valleys. The hard rocks left behind can form mountain glaciers: hills that make the valley higher and much more narrow. In history, mountain glaciers were strategic venues for homeland defence, like the Fort Queyras.

Often confused with wasps, hoverflies are diptera (a single pair of wings). They have the distinction of having sharp changes in direction, and to practice hovering. They are harmless and very useful. The larvae feed on aphids and protect gardens. As for adults, they feed on pollen and nectar. They play an important role in pollination. Their presence is evidence of biological and ecological wealth. These are very fine quality and environmental diversity indicators. Inventories help to guide management, especially forestry, as it was developed in the National Nature Reserve of Lake Remoray in the Doubs and Jura.

Mount Pointe de a Selle is the last summit of Queyras said to be of "limestone". Composed of jurassic limestone,it is surrounded by soft rock (gypsum to the west and shiny schist to the east). During the last ice age, the glaciers have carved the softer rocks. Here, they have scraped the gypsum and the schist. In their moving, they left the less easy to erode rocks.

The sinkholes are circular depressions in the ground. The disintegration of surface limestone (reference made here to gypsum) causes a weakening, leading to its collapse which may be slow or sudden. Their bottom, often waterproof and rich, promotes the development of vegetation. It is advised to be careful going into this "Swiss cheese".

The gypsum plaster stone, is a rock which comes from salt crystallisation. It forms in lagoons where salt water is trapped. The water evaporates and leaves salt masses that crystallize. This rock is very sensitive to the action of water. The hydration and dehydration causes increases or decreases of the volume of Gypsum. This characteristic can lead to collapses. The significant erosion of white ruin ravine and sinkholes are examples.

After all that exhausting descent, another break before heading for the track? Montbardon offers a view of the gorges of the Guil and the comfortable places to enjoy it. A craving? Go to the Fromagerie (cheese shop) in the village centre. It processes in particular goat milk from goats that are year-round in the village.