Parking area on the Ain/Jura border near a sharp bend, approximately 2 km after Tabagnoz coming from Les Rousses, approximately 4 km after the Vattay Nordic Centre coming from the Col de la Faucille.
(S/E) Take the track at the end of the car park; the route follows the yellow markings.
(1) At the three-way junction, take the left track and leave the one leading to the Greffière chalet. Pass the border marker to enter Switzerland. You will come to a tarmac road.
(2) Turn right towards the pastures. Further on, leave the road on your left that leads to Sonnailley au Prince and continue towards the Grand Sonnailley chalet. Continue along the road, passing close to Petit Sonnailley, until you reach a fork.
(3) Take the road on the left until you reach an intersection (sign).
(4) Turn right onto the path that climbs uphill. Go up the slope and pass through a small gully.
(5) When you reach the corner of a low wall, follow the path to the left (signposted). Go through a gate and follow the slope to reach a small, partly shaded ridge that provides shelter from the wind. Follow the ridge until you pass a low wall and come out at a small pass just before the summit.
(6) Continue north-east to the summit.
(7) Return to the small pass.
(6) Follow the marked route to the left (south). Descend to a cluster of fir trees 100 m below.
(8) Pass this group, locate and turn right, following a red mark. Continue south-west until you pass the low wall at the designated crossing (yellow and red mark).
(9) Descend opposite (south-west) into the grassy valley (faint tracks). Join the ascent route at the corner of the low wall.
(10) Follow the outward route in reverse to the car park (S/E).
. But on the other side, it was very beautiful.