A bit of legend and adventure are part of the walk.

From the village of Ollomont, continue to the hamlet of Rey where you can leave your car in a parking lot. Here you cross a bridge and go up to the left towards the Locanda delle minere where are the signs of the Alta Via 1. After a few bends you come to cross the dirt road of the ru du Mont and here you have to pay some attention: you must follow the flat dirt road to the left even if there are visible indications of paths 1 both triangular and round (1 triangular = Alta Via; 1 round ring route that climbs with a lot of difference in height and much longer). At this point continue through the woods until the path becomes more adventurous with stretches of path carved into the rock; even if there are protections and metal ropes to hold on to for greater safety it is necessary to pay attention. Cross a small stream without a bridge looking for the most convenient place to ‘jump’. After a short stretch you reach the entrance of the tunnel from where the waters of the ru du Mont arrive. The gallery is normally not illuminated so it is essential to have a battery-powered torch with you, from the entrance you can see a distant white dot: it is the exit 700 meters away. The water flows inside a canal with a wall and protective net and its noise accompanies the whole crossing. Exiting the tunnel, continue right for about 300 meters until you reach the paved road. From here the view is spectacular on Becca di Nona and Monte Emilius but above all on the enchanting solitary church of Chatelair on a small promontory surrounded by greenery. For the return, if you want, you can return by choosing the ‘pedestrian path’ indicated on a special panel, but this path is much longer, with much more difference in height as it passes from the Fontine Visitor Center in Frissonnière di Valpelline, we therefore recommend the return on the same itinerary. The legend tells how this ru, which in some places is dug on the steep walls of the mountain, was so precious that it was guarded by a guardian and a white snake (actually a protective fairy). The guardian’s substitute killed the snake and from that moment the canal began to be destroyed. Only the tunnel restored the passage of the precious waters.