Central problem on the boulder 5m to the left of Tenochtitlan, 40m after Le Smile, in the sector Arcades.
Access : from the parking lot of La ferme du Montrouget, pass the main sector, take Le Chemin de la Roche qui Tourne (GR) for 40m to the East and follow a small path up the slope to the South for 150m. The boulder is at the end of the valley, 40m to the North after Le Smile.