Park at the top car park at Hautacam. Observatory and inn.
(S/E) From the large car park, head due south and, after 50 m, turn left, heading due east, onto the track to quickly reach the Col de Tramassel or Col de Buraou.
(1) Leave the track and continue to the right, heading due east, uphill to reach a car park near the Col de Moulata.
(2) Turn onto the path on the left, passing beneath the Naouit ski lifts. Follow a hairpin bend to the right to reach the top of the ski lifts.
(3) Cross the ridge and keep to the hillside to reach the junction with the Discovery Trail.
(4) Turn left onto this path and head for the Hourquette d’Ouscouaou.
(5) Caution here: this is where the difficult section begins, as the path is not marked; this section is strongly advised against for children. Note: the path shown on the IGN map very quickly turns out to be a network of sheep tracks. Navigate using the map; the GPS track is very useful here. Then rejoin the path.
(6) Follow it as it climbs gently to reach the highest point.
(7) Continue on and, via a wide bend to the right, reach the stream feeding into Lac des Plagnous. Follow it along until you emerge at the lake.
(8) Carry on along a good path to reach the area above Lac d’Isaby.
(10) Pass by the Cabane de Picourlet.
(9) Carry on straight ahead and, a few hundred metres further on, rejoin the Discovery Trail.
(11) Turn right onto it, following a gentle climb, and reach the junction you passed on the way out.
(2) Turn left and follow the outbound route in the opposite direction to return to the car park at the top of Hautacam (S/E).