On leaving Cauterets, follow the road to Pont d'Espagne. The road (D920) becomes one-way and has two large hairpin bends. Stop on the right-hand side of the second hairpin bend on the left, at the end of the one-way section.
(S) Park in the tree-lined car park (altitude 1044m), next to the abandoned spa (Des Griffons). There is a wooden-framed building wedged into this hairpin bend.
Walk along the spa on your left. Take the flat path heading north (Chemin Demontzey). It overlooks the D920 towards Cauterets. Intersection with the road leading up to Cambasque. The easiest option is to follow this road for 1.2km.
The other option is to continue straight ahead at the junction with this road. The path descends slightly, and at the next crossroads, take the path (GR®10) on the left which leads back to the road.
(1) Follow thisGR®10(red and white markings) to the track (1481m).
(2) Turn left and continue climbing this track for 300m. Turn left and leave the track, following the red and white markings.
(3) When you reach the first lake (Lac Noir, 1,896 m), take the track on the right (offthe GR®10) towards a restored hut. Leave the track after 250 m, at the bend, and turn left, heading due north. Follow this well-marked path.
Rejoin theGR®10after a kilometre's climb through the mountain pastures. Continue towards the Col d'Ilhéou (2,242m).
Note: If you encounter any problems, head directly to the refuge by turning left onto the track for 800m.
(4) At around 2100m, turn right to head due east. The path is almost flat.
(5) At the altitude of 2161m, at the end of the ridge, turn left heading north-west. Now follow the Crête du Lys, the path climbs towards the orientation table at 2304m. The view is splendid.
Then head towards the Col l'Ilhéou by taking a path heading due west, which descends slightly before climbing back up to the pass.
(6) When you reach the Col d'Ilhéou (2242m), a superb view awaits you. Then turn back 200m and follow the red and white markings ofthe GR®10. Descend to the right, towards the Cabane d'Arras (2185m) and then towards the Refuge d'Ilhéou
(7) Arrival at the refuge and Lake Ilhéou (1988m). A well-deserved rest awaits you. In the evening, this place is very quiet and pretty, with a bird's eye view of the valley you climbed up.
Descend back to the starting point (E).