Lake Bastampe from Agnouède, Luz-Saint-Sauveur

The route starts at an altitude of 1,058 metres near the Luz-St-Sauveur thermal baths, on the left bank of the Gave de Gavarnie, via a small road leading to the hamlet of Agnouède. There are several parking spaces for 3 to 4 vehicles, just before the road crosses the Ruisseau Mensongé.

(S/E) Take the track that climbs up to the left of the road (don’t be put off by the ‘Private Property’ sign, which only indicates that cars should not enter). 240 m after the start, turn left onto a narrower track leading to the Agnouède house. Immediately, to the right of the buildings, take a small path that climbs between the fields, heading due south, then temporarily due west, and then due south again. The yellow markings begin here, though they are rather sporadic.

(1) 500 m past the Agnouède buildings, the path makes three hairpin bends (right, left, right) to avoid heading towards the Moura farm, then continues its ascent north-north-west. In the Lahué area (IGN map), another hairpin bend directs the path southwards, deep into the undergrowth – an area formerly used for farming, criss-crossed by a network of small dry-stone walls. The path passes beneath the high-voltage power line as it climbs gently southwards towards the Cabane d’Estarous.

(2) As you approach the Ruisseau de Badet (which flows down from the lake of the same name), the slope becomes steeper and there are more and more hairpin bends. The path crosses the stream via a concrete footbridge. The route continues south-west. In 1 hour 15 minutes to 1 hour 30 minutes, you will reach the Cabane d’Estarous.

(3) Continue along a path, still signposted, heading roughly south-west. You will reach the concrete water collection channel at an altitude of 1,920 m.

(4) NB: here you have the choice of taking the path on the right (easier but slightly longer) or the one on the left, which is more challenging (with handrails and exposed sections, though not particularly difficult), but quicker; this is in fact the service path for the water collection channel’s hydraulic installations. This route opts for the ascent on the right and the return via the handrails.

So turn right and follow the collector along the contour line for about 180 m, following the yellow markings. Look for steps to help you climb up the collector easily and continue along the path 30 to 50 m above it. The path is not always very well signposted, but it is clearly marked and well cairned. Take note of the unnamed pass on the left, which you should head towards; your destination lies beyond it. You will cross several tributaries of the Ruisseau Lassariou – the flow of which varies with the season – including, in particular, a very beautiful little waterfall (flowing in August 2026).

Cross the Culaus d’Aubuste from north to south, a vast, steep expanse with sparse vegetation consisting of shrubs, thorny bushes and mountain grasses, and occasional scree. Climb to an altitude of approximately 2,080 m before descending to 2,000 m, where the path joins the one to be taken later on the descent, just below the spillway of Lac de Bastampe.

On this section, you’ll pass a concrete structure bearing the inscription ‘Lac de Bastampe 30 Min’, which is misleading, as there are still a good 40 to 60 minutes of climbing ahead. In the distance, on the other bank of the Gave and therefore on the opposite slope, you never lose sight of a curious and imposing building. This is a pumping station for the penstock leading to the Pragnères hydroelectric power station, at an altitude of 1,690 m.

(5) At the fork, continue uphill to the right; the lake is not far away. Make your way through a jumble of large boulders to reach the spillway, then a first small lake, just before Lac de Bastampe. On the isthmus separating the two lakes, discover this gem of a lake. Walk out onto the isthmus to admire the lake in all its splendour and, above all, the verdant islet and its crooked pines, which are the source of its reputation and charm. Take your time walking through the Bastampe glacial cirque, which created this lake, and enjoy a lovely break.

(6) Retrace your steps to the fork in the path.

(5) Turn right shortly after the boulder field and follow a well-marked cairned path. Heading broadly due north, reach the water collector just before the Ruisseau de Lassariou at an altitude of 1,860 m, where it emerges from an underground section.
NB: the concrete water collector emerges from its underground section via a concrete structure and a watertight door, just before a weir on a tributary of the Lassariou.
Then take the path that follows the concrete water collector above ground along the contour line, heading north.

On the left bank of the Lassariou, the culvert goes underground again and the path then skirts the rocky outcrop along a ledge, becoming more exposed. However, sturdy stainless steel cables provide a secure handhold. Nevertheless, this section may be daunting for those prone to vertigo. The path then continues alongside the culvert until it reaches the junction from the outward journey; the circular route is now complete.

(4) Return to the car park by following the route in the opposite direction to the outward journey (S/E).

This description relates to a summer hike undertaken as a group in August 2026.

In winter, only attempt this route if you are fully proficient in snowshoeing or ski touring, and in the use of crampons and an ice axe.

Parking at the start
(S/E) At an altitude of 1,058 m, at Les Granges d’Agnouède, in a small car park. This is not an official car park marked on road maps. It may be full during the peak summer season. Park as carefully as possible at the side of the road, ensuring you leave enough space for farm machinery to pass. Do not enter the track marked “PRIVATE PROPERTY”!

Estimated time
We completed this route at a very leisurely pace in 8 hours, including breaks, lunch, a dip for our feet and photo stops, setting off from the car park at 8.25 am. Allow between 2½ and 3½ hours (usually) to climb up to the lake for adults in good physical condition, and a maximum of 2½ hours for the descent.

Difficulty
The route is reserved for walkers accustomed to mid-mountain terrain; it can serve as a test for less experienced walkers, who should take their time. The return via the cliff path and the cables is not suitable for children under 7 or elderly people with limited mobility. It is classified as ‘Difficult’ because, although the elevation gain is only around 1,000 m, the distance is considerable and the terrain is wild. The IBP Index is 112 HKG, which corresponds to a ‘Very Difficult’ route for a walker of average fitness.

Alternatives:

• the route via Yer de Prat is unknown; is it passable?
• Ascent to Lac de Litouèse and the hut, then return via the Soum de Liane de Castillon and the Sapinière de Noubasséoube

Water sources
There are no sources of drinking water along the route. In spring and summer, meltwater from snowfields, springs, lakes, rivers or surface runoff cannot be guaranteed to be safe to drink, even though there are no herds grazing in the summer pastures in this area above the Cabane d’Estarous (3). Bring at least 2 litres per person and/or a filter or purification tablets.

Shelter
There are several shelters along the route: the Cabane d’Estarous (3) and the structures at the entrance and exit of the water collection channel (between (4) and (5). There is no reliable shelter in the event of a storm at Lac de Bastampe.

Equipment
In summer, bring the usual equipment for a mid-mountain hike: walking boots, walking poles, suitable clothing, rainwear, water, food, a survival blanket, a knife, a compass, a map, a whistle, sunglasses, a hat, sun cream, UV-protective lip balm… A GPS (or a smartphone with the Visorando hiking app) can prove very useful.

Crowds
At weekends in spring and summer, the route is very busy as far as Lake Bastampe, but much less so beyond that point. 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.

Check the weather forecast before setting off.

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

The village of Gavarnie, the cradle of Pyrenean mountaineering (alongside Cauterets).

The Cirque de Gavarnie, its historic inn (now a 4* hotel) and its famous waterfall.

Pyrenees National Park:

The Pyrenees National Park, also known as the Western Pyrenees National Park, established by Pierre Chimits in March 1967, is one of France’s eleven national parks. It is situated in the south of the country, in the western part of the Pyrenees mountain range, straddling the departments of the Hautes-Pyrénées (now part of the Occitanie region) and the Pyrénées-Atlantiques (now part of the Nouvelle-Aquitaine region).

Visit the PNP website