Pics d'Ayous and Pic de Larry circular via the Vallon d'Aas de Bielle

From Laruns, head towards Spain via the Col du Pourtalet. After the hamlet of Gabas (in the municipality of Laruns), at a hairpin bend with a small car park on the left, turn right towards Lac de Bious-Artigues (the road is closed in winter, which explains the ‘No Vehicles’ sign that may be misleading).
There are two car parks available. The first is on the shores of Lake Bious-Artigues and the other is a little further down the road before you reach the lake.
Set off early, otherwise you’ll have to park at the “lower” car park, which will add an extra thirty minutes’ walk.

(S/E) From the car park (elevation 1304), make your way to the foot of the Bious-Artigues Lake dam at its western end by following a section of^{the GR®®10}and^GR®®108, then taking one of the many footpaths.
Continue for a few dozen metres and follow the path across the arch dam itself (not visible from the car park).
Continue along the path that circles the lake anti-clockwise.

(1) At the fork, turn right onto the path which climbs steeply through the forest, alongside the Ruisseau d’Arec d’Aas. From here, the Vallon d’Aas de Bielle begins.
It is sometimes described as a ‘hidden valley’ or ‘secluded valley’, in contrast to the classic, extremely popular Ayous Lakes route.
The path meets several side branches at the 1491 mark; continue straight on.
The path climbs just over 200 metres before leaving the shaded part of the valley.
The landscape changes completely. The view is wide open as you approach the first hut in the Vallon d’Aas.
To the right, the south-facing slopes of the Soum d’Aas (elevation 2,427) are quite arid, with low vegetation and stony ground. To the left, further down, lies the valley floor, with the Arrec d’Aas and a metal ‘cuyalas’ (enclosure) for penning up sheep at night.

(2) A short stop at the Vallon d’Aas shepherds’ hut allows for a brief rest (about 1 hour after setting off).
Carry on straight ahead, climbing. The path continues to climb steeply.
At the 1,825-metre mark, you’ll cross the main stream of the Arrec d’Aas for the first time.
(On the other bank, you can leave the path and head towards the next ravine, as it is not advisable to cross here).
Following the ravine, you’ll reach the second crossing, here near a secondary tributary of the main stream, at 1,930 m.
The ruins of a metal ‘cuyalas’ bear witness to the force of the snow avalanches in winter.
From there, the path, which had generally followed a west-south-westerly direction, turns south-west, running beneath the north-south ridge extending from the Soum d’Aas and joining the Pic d’Ayous.
Reach the Col d’Aas de Bielle (elevation 2,098).

(3) The pass provides a link to^{the GR®®} 10 from the Chemin de la Mâture and the Baigt de Saint-Cours in the Upper Aspe Valley, leading to Lac de Bious-Artigues in the Upper Ossau Valley.
The ridge leading to the Pic d’Ayous is only accessible by climbing.
Descend south-west towards Baigt de Saint-Cours, following a fairly narrow but well-marked path, with a 50-metre descent.
The path then climbs between the rocky outcrops, through a small valley (still snow-covered at the end of May 2022 but perfectly passable without equipment).
Reach the small pass at elevation 2212 between the Col d’Ayous and the Pic d’Ayous (which was also still blocked by a persistent snowfield at the end of May 2022, but equally perfectly passable without equipment, except for a pair of walking poles as both sides are exposed).

(4) Follow the ridge due east to reach the Pic d’Ayous (elevation 2288).
(You can easily follow the ridge northwards to the 2264-metre point, overlooking the Col d’Aas de Bielle, which you passed earlier).
After spending as much time as you wish at the summit (see the section ‘During the hike or nearby’ below), turn back to the small pass you have already crossed.

(4) Continue straight on, descending whilst staying on the ridge, heading south-west. Reach the Col d’Ayous at an elevation of 2,188 metres.

(6) A signpost marks the pass, as do the^GR®®10trail markers, as this is a junction on the route (to the right towards the Chemin de la Mâture, to the left towards the Ayous Lakes).
Carry on straight ahead, slightly below and to the left of the ridge, still heading south-west, then quickly turning south.
Follow the very gentle ridge line in this way.
400 m after the pass, you come to a rocky outcrop on the ridge.

(7) Do not cross it, but descend to the right into a small hanging valley, along a narrow, non-exposed path.
Once at the bottom of the valley, look for the best route – taking into account the presence of any late snowfields – to climb up to the left onto the ridge leading to Pic de Larry at elevation 2337 (the end of the hike).
There are no exposed sections, as the ridge is well-rounded.

(8) Turn back for the descent until you rejoin the Col d’Ayous ridge at the rocky outcrop.
As soon as possible, turn right into the hollow below the Col d’Ayous.
Depending on the season, cross a small snowfield or a network of small meltwater streams (by late summer everything is completely dry).
Join the^GR®®10, which descends towards Lac Gentau. Further down, you’ll come to a junction that you mustn’t miss.

(9) The^GR®®10continues along the gently descending contour line. Ignore the south-facing path, which descends much more steeply towards the refuge.
After a few hairpin bends, you’ll reach Lac Gentau at an elevation of 1,947 metres and a very clearly marked junction.

(10) Turn left onto the^GR®®10, where the red and white markings resume. Leave Lac du Miey on your right. Descend via the Waterfall du Miey pass until you reach Lac Roumassot and the shepherd’s hut at 1,850 m.

(11) Continue along the^GR®®10until you reach the Col Long d’Ayous clearing. Instead of continuing on the^GR®®10, leave the path on the left and head towards the (main) Col Long d’Ayous hut at 1,698 m.

(12) Continue down the valley towards the forest.
Enter the forest. Pass the spring at 1,650 m on your left.
Continue down a gentle slope through the forest for just over one kilometre, with a descent of 240 metres.
You’ll reach a first junction with a path around the lake; turn left. You’ll reach a second junction with the main path around Lake Bious-Artigues.

(13) Turn left to walk round the lake in a clockwise direction. Return to the junction by the lakeside.

(1) Carry on straight ahead in the opposite direction to the outward journey, cross the dam’s arch and then head back to the car park (S/E).

This description covers a so-called ‘summer’ hike undertaken solo in the spring (late May 2022). However, there are still a few patches of snow to cross along the route, though these can be crossed without equipment.
Even though half the route is unmarked, the paths are perfectly visible. You can complete this route using just the map; a GPS or the Visorando app on a smartphone are useful, but not essential.
__The aim is to get away from the crowds by taking a less-travelled route.
However, this route is only suitable for those wishing to climb the Pic d’Ayous and/or the Larry, not for those simply heading for the Refuge d’Ayous, as it adds 70 per cent more elevation gain!__

Parking at the start
The D231 road leading to the car parks at Lac de Bious-Artigues is in good condition but not very wide. It is crossed by numerous drainage channels, which must be crossed slowly but are not a problem.
In spring, there are no attendants and no charge to pay. Once you reach the^first car park at Bious-Oumette, it is unclear whether the second car park at Bious-Artigues has any spaces available; many vehicles make the return journey for nothing. Checking whether these cars are returning before heading for the^second car park saves you from wasting a quarter of an hour, or even more, in the car, and allows you to make the most of that time by walking from the^first car park!

Estimated time
I completed this route in just under 7 hours, including breaks and a picnic, setting off from the car park at 9.45 am. This is a fairly tight estimate. Allow between 7 hours 30 minutes and 8 hours 30 minutes.

Difficulty
Rated as a ‘Medium’ hike; the paths are all clearly visible and are sometimes signposted^GR®®10. The landmarks (passes, peaks, lakes) are visible from a distance. There are no exposed sections and the gradients are reasonable.
However, you’ll need stamina to cover a distance of nearly 16 km and a climb of 1,170 m, which is neither too gentle nor too steep.
The IBP Index (an automated system for assessing the difficulty of a route), a partner of the FFRandonnée, is 135 HKG, which corresponds to a ‘Medium’ route for a hiker with a high level of fitness.

Water points
There are no drinking water points along the route.
There is a source of drinking water at the Refuge d’Ayous, 450 m from WP (9).
Springs, lakes, rivers and surface water are not guaranteed to be safe to drink due to grazing livestock.
Allow 1.5 litres per person.

Shelters

• The Cabane d’Aas de Bielle has a tiny section open all year round, which can temporarily accommodate 6 people standing inside, in the event of a storm, for example.
• The Ayous Refuge, 450 m from WP (9), can accommodate large numbers of walkers all year round, both day and night. For an overnight stay during the staffed season (late May to early October), barring emergencies, you must book well in advance to secure one of the 47 places. Outside the staffed season, there are 12 places, which are sometimes snapped up quickly, given how popular the site is.
• The Col Long d’Ayous Hut can accommodate around four people all year round, both day and night.
• However, in an emergency, you can also take shelter against the walls of any of the huts mentioned.

Equipment
Bring the standard kit for summer high-mountain hiking: 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 ensure a truly safe hike.

Trail traffic
In summer, the route is extremely busy from (S) to (1).
Beyond that and up to the small pass of Ayous (4), you may come across a few rare hikers.
Between (4) and (6), the number of walkers increases significantly.
Between (6) and (7), you generally won’t come across anyone.
Between (6) and :11::, it’s extremely busy again, especially on sunny late afternoons at weekends or during school holidays.
Between (11) and (1), you’ll rediscover the tranquillity of solo walks.
The vast majority of this route is therefore in 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 updated on any changes by text or phone.

Météo-France Mountain Forecast
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:
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Lake Bious-Artigues
This is an artificial lake, with a thin-arch dam built between 1953 and 1957. Standing 50 m high, with a head of 285 m and a capacity of 5.1 million m³, it submerged part of the Bious-Artigues plateau, replacing it with the lake.
The dam and the hydroelectric power station are owned by SHEM (Société Hydroélectrique du Midi).
‘Bious’ means ‘waterhole’ in Gascon. ‘Artigues’ refers to areas cleared in the Middle Ages, which created new clearings at the time.
Source: Wikipedia

(2) Vallon d’Aas de Bielle hut (1,668 m)
A charming shepherd’s hut, nestled in a rock hollow, with a terrace, table and benches. It is used by shepherds in summer. A small open area can serve as shelter for six people standing upright in the event of a storm.

(3) Col d’Aas de Bielle (2,098 m)
The stream flowing on the upper Aspe Valley side is the Baigt de Saint-Cours. ‘Baigt’, pronounced ‘Batch’, means ‘valley’ in Gascon.

(6) Col d’Ayous (2,188 m)
It is not uncommon to come across quite a few people here from the fine weekends in May onwards, as it is a junction of several paths, including the^GR®®10, which you rejoin here.

(8) Pic de Larry (2,337 m)
Virtually the same view of the surrounding peaks as from the Pic d’Ayous, but from a different, very interesting angle.
Views of the Pic du Midi d’Ossau and the Ayous Lakes, particularly Lac Bersau (2,100 m). In late May 2022, the latter was still partially frozen.
The scenery is magical!
There is no one on this summit, whilst numerous walkers are thronging the Col and Pic d’Ayous.
See also the winter route on the Pic de Larry, a hike by the same author, MCTOUL.

(10) Lake Gentau (1,950 m)
From here, at weekends and during school holidays, if the weather is fine, from May onwards, there is a steady stream of walkers and hikers coming from the Lac de Bious-Artigues car park.

Between (10) and (11) is the Miey Waterfall.
Don’t miss the chance to take a few photos of this magnificent waterfall! It is also the only one of note along the route.

(11) Lac de Roumassot shepherd’s hut (1,850 m).
Renovated in 2021, sheep’s cheese is made here during the summer.
It has replaced the old stone Roumassot hut, which is open all year round.

(12) Col Long d’Ayous Hut (1,698 m)
Known as ‘d’En-Bas’ to distinguish it from the very nearby hut known as ‘d’En-Haut’. This hut has three small areas: a fire pit, a storage area and an upper level for sleeping. Capacity: 4 people. Rustic condition.

Between (12) and ::12: Crossing through the forest.
This alternative route isn’t really a shortcut in terms of distance or time. However, it does offer very refreshing woodland scenery and, above all, is completely uncrowded, whilst the crowds jostle along the classic^GR®®10route and its sections of concrete track.

(13) Lake Bious-Artigues.
Walking round the lake on the left-hand side in a clockwise direction adds a little to the distance, but allows you to continue the walk in solitude, rather than amidst the crowds on the^GR®®10.