Park at the Col des Marrous car park.
(S/E) From the car park, cross the road (D17) and walk alongside the large buildings of the former asthma treatment centre until you find a track (GR® de Pays) that heads straight ahead before entering the forest via a steep path. At the end of the forest, you will come to a flat area with a fence across the path.
(1) Do not go through the barrier and leave theGR® de Pays, which continues opposite along the flat grassy track. Climb up to the right, behind you, along a path that winds its way through the ferns, sometimes churned up by adventurous wild boars. A gap in the forest offers a glimpse of the buildings at the pass. The climb continues through the undergrowth in the beech forest. The path has been levelled, probably by a forest bulldozer, before reaching a flat area with a crossroads. Be careful!
(2) Do not continue on the track opposite, which descends slightly, but turn left to continue climbing. If you are unsure about the route, don't be fooled: continue along the flattened track, always climbing. The markings seem to have long since been erased from the trees and from memory! The route gradually rejoins the ridge before passing the discreet Col du Plandot.
Head right again, continuing uphill. The original trail has disappeared due to logging. Continue along the flattened track, which curves to the left before you come to a strange crossroads where you have a choice: either turn right onto the flattened track that leads directly to the Col d'Uscla, or turn left to pass the Cap des Trois Termes and its viewpoint (optional route).
Follow a grassy "track" that turns slightly to the right and you will come to a fence that you need to climb over. Continue for a few metres straight ahead to find the old path! Turning right, in the middle of the ferns, the path immediately reaches Cap des Trois Termes: sign at an altitude of 1,278 m.
(3) Continue along the fence on the path which rejoins the flattened track further on. Go straight ahead and, after a final steep climb, descend to the Col d'Uscla.
(4) Go straight ahead (sign). Be careful! As soon as you enter the forest, the path branches off to the left, along the fence, and is even signposted in places! The route is pleasant through this magnificent beech forest. A little higher up, join a track coming from the right and another crossroads.
(5) Turn left to continue climbing. Make sure you remember this junction for the return journey! Gradually, the landscape opens up and the views become magnificent. The track comes to a barrier.
(6) Leave the track on the mountainside to your right, which will be the way back. Go through the barrier and continue climbing along a grassy track that gradually opens up the horizon. The climb is tough. Fortunately, several flat sections offer a welcome respite between the steep slopes! Finally, after one last climb, you will reach Cap du Carmil.
A magnificent 360° viewpoint! The view is spectacular and breathtaking! From the plains far below to the peaks above. Montcalm and Estats, the highest peaks in Ariège, but also Le Valier and many others..
(7) From here, you have two options: either turn back to the barrier at the junction you passed on the way up, or explore the beech forest a little further, as shown on the map. To do this, go through the fence and descend to the right along the fence towards the Col de Péguère. Don't miss the junction! If you pay attention, it's the only barrier since the summit. The signpost is very discreet and there is no sign.
(8) The track veers off to the right and continues along the mountainside through the beech forest. After passing three watering troughs, go through the gate to find the gate-crossing from the outward journey at the edge of the forest.
(6) Descend to the left to retrace your steps, making sure not to miss the junction marked on the way up, until you reach the Col d'Uscla.
(4) Leave the track you took on the way up and take the one that opens up a little to your right, between two wooden posts. The grassy path is pleasant on the mountainside and offers magnificent views of the green valley of the Col des Marrous. The descent then begins and leads to the Col de la Serre (1,153 m).
(9) A sign clearly indicates the direction: left! The route enters the beech forest again and the moment is magnificent. The beech trees form an incredible hedge, and the earth of the path seems to be filtered, making it surprisingly soft to walk on. What bliss! Descend a little further and you will come back to the first crossroads of the morning with its fence gate.
(1) Continue along the track opposite, which descends to the Col des Marrous and the car park (S/E).