Pic de Labas and Tour des lacs des Oulettes d'Estom Soubiran

Head to the Ossoue Dam in the commune of Gavarnie-Gèdre, then to the start of the hike 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 in red and white.

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, past the twin waterfalls of the Gave d’Ossoue and the Ruisseau de Pouey Mourou (pouey = hillside in the Bigour 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 its ascent.

(1) At 2,303 m, the path splits into two. To the left, it heads towards the Refuge de Baysselance (2,651 m) and Pique Longue du Vignemale; to the right, it heads towards Lac des Gentiane, the pass of the same name and the Refuge d'Estom. 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 hikers heading up to Lac des Gentianes or setting off 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 on 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 left off-trail, first along the stream, then through a cascade 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, without tackling the steepest sections.
Near the ridge (2686 m), at around 2675 m, start a series of switchbacks up the slope to find the best route through the rocky outcrops, grassy slopes and scree. 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 Pic de Labas (labas = steep cliffs in the Bigour dialect), a long, flat ridge that is easy to traverse and where you can take a safe break. Two large cairns mark the summit: an eastern cairn, via which you arrive, 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 rocks covered in small pebbles rolling underfoot; high risk of falling!

Head for the small pass between the Labas and its sugar loaf. At the small pass, another exceptional view of the lake 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 roll like water...

At the bottom of the couloir, head towards 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 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 the 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, flowing down from the lakes, beneath the towering presence of the Pic de Pébignau on the left.

(5) Reach a 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) Reach the^first large lake on the route, Lac de Labas, at 2,281 m. It is dominated on the right by the Tuc de Labas (tuc = mound in Bigourdan) and the Pic de Labas, which you passed earlier. Go round it on the right bank, continuing along the path, which is always clearly visible and sometimes marked with cairns.

(7) Reach the spillway of the largest of the lakes, Lac des Oulettes d’Estom Soubiran, at 2,387 m. Go round it on the left bank, 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, without vegetation in the Bigour dialect) at 2,445 m. It is one of the smallest of the major lakes, but it is flanked by two small satellite lakes, not to mention Lac de Malh Arrouy, a little 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 serving as a spillway.
A small island sits near the northern shore. It is idyllic and very secluded... The path climbs further to the right to cross the Estom Soubiran plateau, so curiously streaked with 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 series.

(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 Lac des Gentianes, which you will reach shortly. The path is not clearly visible; do not head straight for the lake and do not stray too far to the left of the rocky ridge. Reach Lac des Gentianes and its large campsite 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 secluded surroundings of this high-mountain lake, the highest in the Ossoue Valley. Off the trail, rejoin the pass path and descend 200 m 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 over 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 on the south face, to avoid getting lost in the rocky outcrops.
The aim is to get away from the crowds by taking a little-used route to 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), this road and the track leading to the dam are in a terrible state, so a vehicle with high ground clearance is recommended.
NB: this road is subject to seasonal closures (autumn and winter); check https://inforoute.ha-py.fr/ before setting off.

Estimated time
I completed this route in 13 hours, due to my co-driver’s health issues, including breaks and a picnic, having left 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^GR®®10. 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 Labas and on the descent).
You need to be fit enough to cover a distance of over 18km and a significant elevation gain of 1,850m.
The IBP Index (an automatic route difficulty rating system), 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, it does not seem as tough as the 1,850m elevation gain might suggest...

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

Shelter
There are no shelters anywhere along the route!

Equipment
Bring standard high-mountain summer hiking gear: hiking boots, suitable clothing, rainwear, sunglasses, water, food, a survival blanket, a knife, a compass, a map, a whistle, sun cream, lip balm, and possibly a walking stick or two. 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.
__
Traffic
In summer, the route is fairly busy from (S) to (1).
Beyond that and up to (2), you may come across a few rare hikers.
Between (2) and (4), you generally won’t see anyone.
Between (4) and (11), it can be a bit busier, especially at weekends.
The vast majority of this route is therefore in an area with little or no traffic.
Whatever the season, don’t forget to let your friends and family know your exact route and inform them of any changes by text or phone.

Météo-France Mountain Forecast
Check the weather forecast.

If you notice any errors in signposting or place names along your route or on the map you’re using, or …, you can become a contributor and report them:
- signage errors, 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 m below, as if at the bottom of a crater, two small lakes covered in a shroud of snow lay in eternal slumber (the frozen lake and the “little lake of the pass”). These are the highest of all the lakes of Soubiran. What horrors surround these lakes! What savagery and desolation! All the rocks look ferocious. These frozen lakes, in the height of summer, in dark, barren and silent gorges, have a sinister and symbolic whiteness. One feels as though one is in the icy vicinity of a corpse abandoned in the polar regions… Water is meant to ripple, to reflect the sky, and to smile.”

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

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

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