Go to the car park at the entrance to the Pont de Moudang campsite, located 8km from Saint-Lary-Soulan on the D929, which leads to the lakes or the Bielsa tunnel (Spain).
(S/E) Leave the car park via a wide path on the right along the Neste d'Aragnouet for 200 m, then take a track on the far left.
(1) Continue along this track, which climbs steadily and runs alongside the Neste du Moudang river through the forest for 5.2 km until you reach a three-way junction. Keep left and cross the Neste d'Héchempy river (1,557 m).
(2) After the footbridge, leave the path on the left that climbs to Les Granges (1,520 m) and turn right, then left after 100 m. Continue along this path, which climbs through the remains of barns and then continues to climb up the hillside to a fork (1,732 m).
(3) Continue left and climb for 1.2 km until you reach a fork (2002 m).
(4) Continue to the right until the next fork (2036m).
(5) Keep left until the next fork (2090m).
(6) Keep left until the next fork (2178m).
(7) Continue to the right and climb several hairpin bends to 2338m.
(8) Keep right as you continue climbing, then turn left to reach the fork for the Col or Port de Héchempy (2375m).
(9) Turn left and climb up to Port de Héchempy, which marks the Spanish border (2,450 m). Descend.
(9) Turn left, descend keeping to the left until you reach Lac de Héchempy (2318m).
(10) Walk along the right side of the lake, then follow the stream downhill (there is no path for 300m). Once you find the path again, continue downhill until you reach a fork (2139m).
(11) Continue downhill on the left until you reach a section of the outward route, which you should follow in the opposite direction.
(5). Turn left at the hairpin bend and continue downhill until you reach a fork (1,813 m).
(12) Continue downhill to the left until you reach a fork at an altitude of 1585m.
(13) Turn right and then immediately left to reach the intersection you passed on the way up, below the Granges du Moudang.
(2) Turn left and descend the path, in the opposite direction to the outward journey, to the Pont du Moudang car park (S/E).