This route for well-trained trailers takes up the entire 20km route, to which is added a 10km loop on the Noirmont.
Leaving the Combe aux Cerfs and before reaching the junction for the Carroz-Jura hut (altitude 1383m), take a small road that leads to Les Platières, then take a marked path at the Combe aux Tassons to La Croue.
From there, a climb awaits you on the Noirmont, passing by the French summit (don't miss the plunging view of the Lac des Rousses!) and then this famous pyramid marking the peaks of the Swiss Jura.
After having enjoyed the panorama, we reach the ski slopes on the French side and take one of them down. After 1500m of descent, we follow the marked path that cuts through the forest, then through the pastures towards Les Coppettes and l'Arzière. Arrived at this mountain pasture farm, there is a slight climb on the right, from where we find the continuation of the 20km and the red and white marking leading us to the hut of Carroz-Jura. The descent then leads to the Combe Grasse et Basseruche.
Estimated average time: 4h30