Refuge du Rulhe - Castelet

(S) Opposite the refuge, take the GR®10, which is also the GRP® Tour de la Montagne d'Ax, to quickly reach a fork in the path.

(1) Keep to the right on the GR®, passing through two new passes with wonderful views of the mountains and lakes. You will arrive at the Col de Behl, at the foot of the Crête des Isards.

(2) Continue along this ridge, following a rather vertiginous path. Be very careful not to slip to the left. From there, continue to follow the GR® and you will come to a rather incongruous and incredible arch, the curved lintel of which was made by hikers. You will then walk along a ridge that circles the Étang d'Embizon, a very wild and little-known lake, before reaching a clearly visible fork just above the lake.

(3) Leave the GR®10 here and keep right on the GRP® du Tour de la Montagnes d'Ax, marked in yellow and red. The path sometimes disappears into the grass, but the markings are always there. Reach the Pic d'Espaillat: the last high point that takes you away from the view of the lake.

(4) Continue downhill to discover a beautiful little wooden cabin in a clearing, surrounded by large summer pastures.

(5) Continue along the ridge. Be careful on this section: even though the markings are clear, you must remain vigilant. You will reach the edge of a forest.

(6) Walk along the edge of the forest, then enter it to reach the Cabane Bretounels clearing.

(7) Turn right, re-enter the forest, pass under Roche Riou Caud, then under Pic des Carmilles. You will come to another clearing: Cabane du Mouscadou.

(8) Continue straight ahead downhill to a new hut located below Font de Tessoula.

(9) Enter the forest again. The descent becomes steeper and steeper, with small switchbacks in the dead leaves. You will come out at the Cabane de Bisort.

(10) Cross the Tessoula stream, continue downhill and, after a few hairpin bends, finish the descent at Place de l'Oum, in the village of Castelet (E).

(E) Here you have several options:
- arrange for a vehicle to take you back to Ax 3 Domaines,
- continue on foot along the GRP®, approximately 3 km further, to Ax-les-Thermes, then climb up to Ax 3 Domaines (shuttle buses available in summer).

Be aware that there is very little water on this section, apart from one or two huts on the map (small stream).
The hike is long and challenging in some parts of the Crête des Isards, and the descent of more than 1,600 metres will make your knees squeak.
The markings are very well done (GRP® Tour de la Montagne d'Ax in yellow and red). However, always remain vigilant as it is easy to stray from the path at certain points. You should be concerned if you haven't seen any markings after 5-10 minutes. They are often on trees or small posts/stones.

(S) Refuge de Rulhe: from here, you have an incredible view of all the lakes and high peaks of Ariège, and more specifically the Aston Valley.
(2) Crête des Isards: the view is well worth the effort and, with a bit of luck, you may spot some chamois.
(3) GRP® du Tour de la Montagne d'Ax: the signposting is recent and very well done. Let's give a shout-out to those who work behind the scenes and allow us to hike in complete safety.
Between (6) and (8): during this long descent, you need to stay alert as the path winds between the trees and sometimes splits. Keep an eye on the markings.