This is a perfect paradise for lovers of flora and fauna. This nature reserve is located between Argentière and Vallorcine and stretches over 3 300 ha. Throughout the walk, 500 species of plants can be observed according to the seasons; there is also a wide variety of fauna such as, chamois, hares and ibexes, that can be spotted along the tour. Finally, the natural spots are signposted by means of some fifteen numbered stations (peat bogs, avalanche corridors, etc.).