From Buet train station, cross the car park to get to signpost 74 and the Nature Reserve information board on the far side of the road. Starting at Le Buet station, there is a « long » ascent to the heart of Bérard valley via the waterfall and the refuge. Passing the latter, the ascent becomes progressively steeper and more technical. In sight of the Col de Salenton, the trail leads into a maze of rocks and boulders. to finally reveal a new valley, greener but wilder. The descent across the alpine pastures of Villy leads to the Moëde- Anterne refuge. Between the lakes of La Montagne de Pormenaz the profile of the terrain becomes more undulating, The often slippery path remains demanding, if one wishes to maintain good rate of movement. At the Chalets de Pormenaz, the trail swings round towards the village of Servoz. The final descent is long but quite fun. After traversing the village, a final, flat, kilometre takes the runner to the life-saving SNCF railway.