Start from Col d’Aspin (1,489m).
(S) Follow the road towards Arreau for about 600m.
(1) At a right-hand bend in the road, after a small stream, head down to the right into the forest, heading due south. After a 50m descent, staying on the left bank of the stream, you’ll reach a damp spot where animals come to drink at the foot of a tree that acts as a water reservoir.
(2) Head left, looking for a fairly wide path that starts on level ground, heading due east. The path narrows and turns south-east. It passes above a collapsed barn on your right and remains below the road. It descends gently, then emerges from the forest and joins the road.
(3) Cross the road and look for a way through the overgrown pasture opposite to cut across the bend in the road. After a 50m descent, join a better-marked path that turns right.
(4) Head right, due west, for 200m, descending towards the road. Cross the road and continue descending due west on the opposite side, along a wide, well-marked path.
(5) After 50m on this path, turn left, heading south-east. Descend for 600m along a wide summer pasture path. Take a right-hand bend after the 1168m altitude, then another left-hand bend. Continue descending along this wide path towards the village.
(6) Join a track and follow it due south, continuing to descend.
(7) Leave the track. Head down to the right along a path that widens into a broad stony track.
(8) Arrive at Aspin-Aure (924m). Take the short street to the left of the church. Cross the Ruisseau de Bucheca via a bridge. Head due south along a very wide stony track, which climbs steeply. At an altitude of 1107m, the track turns right, north-west. A trough in the valley floor provides a chance to fill your water bottles. After this valley floor, the wide path heads due south-west. It continues to climb steeply. Pass the 1147m altitude and enter the forest. The path deteriorates and crosses numerous valley floors. Pass the 1164m altitude. Continue climbing.
(9) Join a wide dirt track (elevation 1206m; on the left, heading towards the Barrancoueu refuge).
Magnificent view; a break may be in order. Head right, climbing up this wide track. Ignore the first track branching off to the right on level ground. Ignore the second track climbing to the right.
(10) Head due west to the left along a wide grassy path. The path then climbs and narrows. It enters the forest. At the first valley, it turns left, heading due south.
(11) At around 1385m, in a clearing, turn right and continue steeply up a wide track. (Ignore the track branching off to the left on level ground.) In a valley, the track disappears. Follow a path branching off to the south-west on the right. The path is poorly marked, but you can see the point you need to head for: La Hourquette d’Arreau.
The path emerges from the forest in places. Stay on the edge. Do not go downhill. Continue climbing, the gradient becoming less steep. Stay well below the ridge on your right. Pass above a ruined hut on your left. Continue climbing gently along a better-marked path.
(12) You’ll reach a signpost. This is the Hourquette d’Arreau (1,538m). From here, you can follow the entire ridge as far as the Col d’Aspin.
(To your left, 300m away, is the Hourquette d'Ancizan, 1564m).
Head right-hand side, due north. A path, very well marked on the ground, goes round the Cap de Sarrat Termé on the left. Continue on more or less level ground and also go round the Broucouze. Pass the 1604m altitude, at an unnamed pass. Continue for 300m, climbing, towards the Plo Del Naou.
(13) Head left, north-north-west, along a well-marked path. Climb a little and then stay at an altitude of approximately 1,670m. Go round Plo Del Naou on the left, following a path that remains level. After having largely skirted around Plo Del Naou, the path heads north-east towards a sort of pass. Cross a few small streams. Descend slightly to join a wide, well-marked path.
(14) Follow this wide path towards the forest. Stay above the forest, along the edge.
(15) Reach the 1,606m altitude and now follow the few remaining yellow markings. Stay on a very wide dirt track. It goes round the left of the Hount de Les Saliès. Pass a series of drinking troughs on your right. Continue along this track, which takes you back to the Col d’Aspin.