From Cauterets, take the Pont d'Espagne road to La Raillére (souvenir shop and restaurant in season), then about 1.5 km further on, take a small road on the left that leads to the car park of the Hostellerie la Fruitière.
(S/E) The walk starts here. Cross a footbridge and follow the wide track for about 4.5 km to reach the refuge and Lac d'Estom.
(1) Leave the refuge on your left and take the path that climbs up the hillside through scree and grass for 2 km. You will reach a junction where there is a snowfield at the bottom of a small valley.
(2) At this point, there are two paths: leave the path to Col d'Arraillé, indicated by a signpost, on your right and take the path on the left, which winds its way up to the top of a small, very steep hill.
The descent on the other side follows a cornice passage for about a hundred metres (avoid if there is still snow).
(3) Take the footbridge over the torrent flowing from Lac de Labas, which leads to a small, very wet plateau. The well-marked trail winds its way between the rocks and reaches the Lac de Labas spillway.
(4) Return via the same route to the car park (S/E).