This trail route, which is not technically difficult, offers a varied course alternating between steady climbs, rolling descents, and flat sections. This diversity allows you to maintain a steady pace for most of the route, while fully enjoying the unique sensations of trail running.

Mostly laid out in the woods, the route is particularly pleasant in summer thanks to the ever-present shade. The wide, well-maintained trails allow for smooth and safe progress, ideal for both beginner trail runners and more experienced runners looking for a fast and enjoyable course.

The route can also be adapted to a shorter version by starting from the Grande Chartreuse Museum, without losing the spirit of trail running or the quality of the terrain. A flexible, natural and rhythmic route, perfect for training or discovering the trails of Chartreuse.


Marking : Trail Marking No. 4 Blue Starting panels are placed in villages at parking areas or visitor reception points. To follow your route, posts are installed at intersections, identifiable by a plaque indicating the name and altitude. Between two posts, painted markers guide the path, though not always. You may also be guided by small directional signs.

Admission fee : Free access.

Opening : All year round daily. Subject to favorable snow and weather conditions.

Step by step description : Starting from the Raidlight/Vertical store, head towards the town hall and cross the road to take the Bois des Lièvres trail located on the other side of Plan de Ville. At the PDIPR Carlinière signpost, continue along the road to the right. At the end of this road in Bernière, turn right and cross the hedge, where you can admire a typical Chartreuse barn. At the next intersection, turn left towards Combe Chaude. Continue on the wide path and cross the stream, staying on the same path. Next, leave this forest track on your left to follow a narrower trail on your right that leads you to the Porte de l'Enclos. Continue on the road towards Saint Laurent du Pont, then the trail will be on your right, leading you to La Correrie, the Musée de la Grande Chartreuse. Cross the museum parking lot to stay on the same road and descend to the Pont des Allemands. The trail continues on the right, following the direction of Habert de Chartroussette. You will join the forest road for the first time, descending before climbing back up the Billon forest road. At the PDIPR Habert de Billon Aval signpost, head towards the Reservoir, continuing in the direction of Notre Dame de Casalibus. After a slight round trip of 400 meters (not included in the route) to discover the Chapelle Saint Bruno, return to the trail towards Bourdoire. Continue in the direction of Sous Mauvernay, where you will find a fairly wide path. For a few kilometers, you will remain in the heart of the Grande Chartreuse forest on the slopes of Grand Som. Two equipped viewpoints on your right offer stunning views of the Monastère de la Grande Chartreuse, nestled in this unique valley. A fairly steep descent will take you above the Musée de la Grande Chartreuse, which you will leave on your left. Take the left trail at the start of the descent on the road. You will reach the departmental road, which you will follow for a few meters before finding the Porte de l'Enclos again. Then take the left trail that you have already followed on the way out. You will cross the stream again, and at Combe Chaude, continue to the right towards La Diat. At the La Diat intersection, turn right to cross the bridge and continue on the left trail towards Pont de la Laiterie. At the PDIPR signpost, head towards the village, and after circling the building on the left, you will find the town hall square, where Raidlight awaits you on the right.

Area : Cœur de Chartreuse