The Combe-Grède, a spectacular chasm in the Jurrassic limestone, literally divides the mountain vertically into two parts. The walk takes 3.5 hours. You can reach Sonvilier by train; a bus service operates from the Chasseral.
The careful planning of a tour will ensure that you also derive the maximum pleasure and enjoyment from it. Please take the time to contact the local information centre and enquire about route and weather conditions before setting off. Your intended trail may be fully or partially closed, depending on the time of year and weather conditions.