Pic de Labas and the Tour des Lacs d’Estom Soubiran

Head to the Ossoue Dam in the commune of Gavarnie-Gèdre, then to the start of the walk above the stone hut near the dam.

(S/E) Take the^GR®®10on the left bank of the Gave d’Ossoue, following the Ossoue Dam along its entire length. Head up the Ossoue Valley, known as the Oulettes d’Ossoue (oulettes = small glacial cirque in the Bigourdan dialect). The path is partially signposted, as it should be, with red and white markings.

Cross the Gave via the footbridge and begin the ascent on the right bank. Pass the^first Ossoue waterfall on your right; the path climbs steeply, carved into the rock. Shortly before 1,994 m, you’ll pass a double waterfall formed by the Gave d’Ossoue and the Ruisseau de Pouey Mourou (pouey = hillside in the Bigourdan dialect); the path continues its ascent. At 2,092 m, the path crosses the Pont de Neige (snow-free in summer) then the Ruisseau de Montferrat and continues climbing.

(1) At 2,303 m, the path splits into two. To the left, it heads towards the Baysselance Refuge (2,651 m) and the Pique Longue du Vignemale; to the right, it heads towards the Lac des Gentiane, the pass of the same name and the Estom Refuge. A signpost indicates the main directions.
Take the unmarked path to the right towards the Gentianes. Follow the Ruisseau des Oulettes valley upstream (the stream flows into the Gave d’Ossoue, which rises near the Baysselance Refuge).

The path is still well-trodden by walkers heading up to Lac des Gentianes or setting out to walk around the Oulettes d’Estom Soubiran lakes (estom = summit, soubiran = south; estom soubiran = the southern summit in Bigourdan). Stay on the path until, just after a slightly exposed section over a smooth, sloping slab, you reach a small plateau, made quite marshy by the Ruisseau des Oulettes and dotted here and there with a few erratic boulders or rockfalls.

(2) Leave the well-marked path and head off-trail to the left, first alongside the stream, then through a waterfall of water and scree. A persistent snowfield may remain here late in the season, but rarely in August or September. You can see the ridge line straight ahead, cut across by the Col d’Estom Soubiran on the right, much lower down.

Keep heading north-east down the slope, avoiding the steepest sections.
Near the ridge (elevation 2686), at an altitude of around 2675 m, begin a series of zigzags up the slope to find the best route through the rocky outcrops, grassy slopes and scree slopes. There are a few cairns and some visible paths. On this south-facing slope, it is rare to find snowfields from July to October. Continue the ascent.

(3) Reach the summit of the Pic de Labas (labas = steep cliffs in the Bigourdan dialect), a long, flat ridge that is easy to walk along and where you can take a break in safety. Two large cairns mark the summit: an eastern cairn, which you approach from, and a western cairn.
From the summit, the 360° view is exceptional. Due south: the border ridge, with the Oulettes d’Ossoue and the Montferrat lakes in the foreground; due north: the ‘Pain de Sucre du Labas’, the Lutour Valley and the Labas Valley; due east: the lakes of the Oulettes d’Estom Soubiran; Finally, to the south-west: the Vignemale massif in all its splendour! To the south-east: the 3,000-metre peaks of Gavarnie and the clearly visible Brèche de Roland. In the distance, Spain!

Continue north of the Pic de Labas, practically behind the large eastern cairn. The descent is tricky but not exposed. The first 50 metres are very steep, on scree, with rock covered in small pebbles that roll under your feet; high risk of falling!

Head for the small pass between the Labas and its ‘sugar loaf’. At the small pass, there’s another exceptional view of the lakes route.
Then take the North-East Couloir, which descends into the Vallon de Labas. The descent is fairly easy over a scree slope of medium-sized stones, but they slide like water…

At the bottom of the couloir, head into the valley coming from the Cols de Labas and then proceed north-west, then north, over another scree slope of large boulders, where the ‘kangaroo’ technique seems the best way to make quick progress! Lac d’Estom at the bottom of the valley begins to come into view. After 1 hour 15 minutes of arduous descent, you’ll reach a proper descending path. This path leads to the Fork in the road at 2,186 m.

(4) Lac d’Estom, its refuge and La Fruitière on the left as you descend; the Oulettes d’Estom Soubiran lakes on the right as you ascend! Turn right. Climb 100 metres along a comfortable, well-trodden path alongside the Gave de Lutour, which flows down from the lakes, with the Pic de Pébignau towering high above on the left.

(5) Reach the first small pool on the Gave, at the junction with the path leading down to Lac d’Estom at 2,240 m.
Continue along the path to the right.

(6) You’ll reach the^first large lake on the route, Lac de Labas, at 2,281 m. To the right, it is dominated by the Tuc de Labas (tuc = ‘mound’ in the Bigourdan dialect) and the Pic de Labas, which you passed earlier. Walk round it on the right-hand bank, continuing along the path, which remains clearly visible and is sometimes marked with cairns.

(7) Reach the spillway of the largest of the lakes, Lac des Oulettes d’Estom Soubiran, at 2,387 m. Walk round it on the left-hand side, crossing the ridge between the two lakes. A quick glance back halfway round allows you to see both of them. Continue along the path.

(8) Reach the spillway of Lac Couy (couy = ‘bald’, meaning ‘without vegetation’ in the Bigour dialect) at 2,445 m. It is one of the smallest in the series of large lakes, but it is flanked by two small satellite lakes, not to mention Lac de Malh Arrouy, situated slightly higher up (which cannot be seen) and which also flows into the Couy. Continue along the same path. Pass a lovely camping spot on a summer pasture.

(9) Reach Lac Glacé at 2,565 m, via the top of a deep gorge acting as a spillway.
A small island sits near the northern shore. It’s idyllic and very secluded… The path climbs further to the right to cross the Estom Soubiran plateau, so curiously criss-crossed by geological veins of all kinds – white, brown, black… The closer you get to the Col des Gentianes, the more lunar the landscape becomes.... Reach the Petit Lac du Col des Gentianes. This is the last lake in the Oulettes d’Estom Soubiran range.

(10) Continue towards the nearby pass. Reach the Col des Gentianes (or Brèche des Oulettes d’Estom Soubiran) at 2,729 m.

(11) Further down lies the Lac des Gentianes, which you’ll reach shortly. The path isn’t really visible, so don’t head straight for the lake and don’t go too far to the left of the rocky ridge. Reach the Lac des Gentianes and its large bivouac area, at 2,642 m.

(12) Follow the right-hand shore of the lake and head for the hillock known as “Belvédère Russel”, to admire the landscape and the secluded surroundings of this high-mountain lake, the highest in the Ossoue Valley. Off the trail, rejoin the pass path and descend 200 metres towards the valley. Reach the plateau below the Gentianes from the route.

(2) Then follow the same route as on the way out, in the opposite direction, of course.

(1) Turn left on the descent and return to the car park (S/E).

This description covers a so-called “summer” hike undertaken as a pair in early autumn (late September 2023). There are no snowfields left to cross on the route, but as the summer of 2023 was particularly hot, you may encounter some in the northern gully of the Pic de Labas or around the Lac Glacé and Petit Lac below the Col des Gentianes.
Even without signposting – and indeed with no path at all for more than half the route – you can complete this route using just a map; a GPS or the Visorando app on a smartphone are particularly useful for the ascent of Pic de Labas via the south face, to avoid getting lost amongst the rocky outcrops.
The aim is to get away from the crowds by taking a little-used route to the waypoint (WP) (4).

Parking at the start
The starting point is at the Pyrenees National Park campsite at the Ossoue Dam. Although the route follows a departmental road (D128), both this road and the track leading from it to the dam are in a dreadful state, so a vehicle with high ground clearance is recommended.
NB: this road is subject to seasonal closures (autumn and winter); please check https://inforoute.ha-py.fr/ before setting off.”

Estimated time
I completed this route in 13 hours, due to my fellow traveller’s health issues, including breaks and a picnic, having set off from the car park at 8.00 am. This is a very generous estimate. Allow between 8.30 and 10.30 hours.

Difficulty
Hike classified as Very Difficult; some paths are visible and occasionally marked with^{GR®®10 signposts}. The landmarks (passes, peaks, lakes) are visible from a distance. However, several sections are off-trail and unmarked, and some parts are somewhat exposed, with a few fairly steep slopes (on the ascent to Le Labas and on the descent).
You’ll need stamina to cover a distance of over 18 km and a significant elevation gain of 1,850 m.
The IBP Index (an automated system for assessing the difficulty of a route), a partner of the FFRandonnée, is 202 HKG, which corresponds to a ‘Very Difficult’ route for a hiker with a high level of fitness.
However, as the total elevation gain is covered in two stages, with a rest period at the summit of Labas between them, it does not seem as tough as the 1,850 m D+ might suggest...

Water sources
There are no sources of drinking water along the route.
Springs, lakes, rivers and surface water are not guaranteed to be safe to drink, due to grazing livestock.
Allow 2.5 litres per person or bring a filter.

Shelters
There are no shelters anywhere along the entire route!

Equipment
Bring standard high-mountain summer hiking kit: hiking boots, suitable clothing, rainwear, sunglasses, water, food, a survival blanket, a knife, a compass, a map, a whistle, sun cream, lip balm and, if necessary, walking poles. A GPS or the Visorando app on your smartphone can complement your kit to make the hike truly safe.
__Add a helmet to protect against rockfalls in the NW couloir (between (3) and (4)) and a head torch in case you need to return at night.
__
Trail usage
In summer, the route is fairly busy from (S) to (1).
Beyond that and up to (2), you may come across the odd hiker.
Between (2) and (4), you generally won’t come across anyone.
Between (4) and (11), it can be a little busier, especially at weekends.
The vast majority of this route is therefore through areas with little or no traffic.
Whatever the season, don’t forget to let your friends and family know your exact route and keep them informed of any changes by text or phone.

Météo-France Mountain Weather Report
Check the weather forecast.

If, on your route or on the map you’re using, you notice any errors in signposting or place names, or …, you can become a contributor and report them:
- errors in signposting, safety issues, conflicts of use, environmental concerns, etc.: click here
- mapping errors, place names, etc.: click here

Just before the summit and at the summit of Pic de Labas (3)
Numerous geological veins of interest to amateur and experienced mineral collectors.

At the Col des Gentianes (11)
In addition to Henry Russel’s comments on Lac des Gentianes and the Vignamale, he also mentioned in passing the Brèche de Pouey Mourou (slightly higher than the Col des Gentianes): ‘To the north, 300 metres below, as if at the bottom of a crater, two small lakes covered in a shroud of snow lay in an eternal slumber (the frozen lake and the “petit lac du col”). These are the highest of all Soubiran’s lakes. What horrors surround these lakes! What savagery and desolation! All the rocks look ferocious. These frozen lakes, in the height of summer, set in dark, barren and silent gorges, possess a sinister and symbolic whiteness. One feels as though one can sense the icy presence of a corpse abandoned in the polar regions… Water is meant to ripple, to reflect the sky, and to smile.”

Option 1
You can opt for the Pic de Labas as a round trip, limiting the elevation gain to 1,100 m.

Alternative 2
You can bypass the Pic de Labas by ascending to the Col d’Estom Soubiran from the waypoint (2).
A long scree slope, which begins with small chimneys requiring caution and the use of your hands for a few metres, leads down to Lac de Labas. You can then follow the lakes clockwise, as described here.

Variation 3
At the Col des Gentianes waypoint (11), you can climb to the Brèche de Pouey Mourou at 2,777 m (48 m elevation gain) for another unique view of the Vignemale Massif.