From Divonne-les-Bains, take the D15 towards Grilly, then at the bend, just where you cross the old railway line, continue straight on towards Mourex. At the hamlet, park in the Mont Mourex car park.
(S/E) From the car park at the top of the hill, follow the signs for Vesancy along a wide downhill path on the left. Keep right at each crossroads until you reach Bois sous Roche.
(1) Turn right, first on flat ground then downhill. You will come to a crossroads.
(2) Turn right and begin a short climb that leads to Carrefour des Chasseurs.
(3) Turn right towards Mont Mourex. Continue straight ahead at the first intersection, then left at the second, after a gate, to reach the summit.
(4) You will come out onto the mountain, marked by an upright monolith. Then follow the trail straight ahead across the mountain pasture to reach an orientation table.
(5) Continue on and keep descending until you reach the starting point (S/E).