Circular walk of the Sentier des Fenêtres via the Grotte des Eaux-Chaudes

Coming from Pau, head towards Arudy, Louvie-Juzon, Laruns, and in the Ossau Valley take the D934 towards the Col du Pourtalet, towards Spain, along the Gave d'Ossau. Enter the hamlet of Eaux-Chaudes. Turn right onto the street running alongside the church, leading to Place Henri IV. Park in the car park next to a fountain.

Please read the description and practical information carefully before setting off on this hike.

(S/E) Continue along this same street, above the Gave. At the last house on the left, turn left and take the stairs that lead to the D934. Cross over and continue almost opposite, along Maison Labarthe and another unmarked old house. Go up Route de Minvielle to Place Minvielle. Turn right above the Source Minvielle water catchment (on the left). Route de Minvielle becomes Chemin de Minvielle, which leads into the forest. This path is marked in red and yellow (Tour de la Vallée d’Ossau) and for mountain biking (VTT 14). Follow it until you reach the Gourzy forest track, which is accessible by car.
Follow it to the left for about 50 metres.

(1) Take a path on the right that joins the track higher up. Follow it to the right. Along the track, numerous traces of forestry work attest to an activity that is still very much alive. Walk until you reach a left-hand bend where there is a sign prohibiting vehicle traffic.

(2) Take a small, well-marked but unmarked path on the right (with numerous red marks on the trees) that starts at the hairpin bend. A sign on a tree indicates the direction of the Grotte des Eaux-Chaudes.

From there, although several paths cross on the map, the trail to follow is very well marked, so there is no fear of getting lost. The path climbs gently through the Bois du Gourzy and, depending on the season, crosses several dry or well-fed streams. Sometimes the path itself is transformed into a muddy stream. On the right, below the trail, you will pass a square-shaped pidgeon hunting hut. On the opposite side of the Gave d'Ossau, on the plateau, you can see the small hamlet of Goust.

(3) After leaving the track, you will reach a first cave at an altitude of 915 m. This is an active exsurgence known as the Petite Grotte des Eaux-Chaudes. Continue along the path at the foot of the cliff. At the end of the cliff is the Grotte des Eaux-Chaudes (or Grande Grotte des Eaux-Chaudes).

(4) Leave the cave on your left and continue along the path, which becomes much less marked and narrower. Reach the outdoor platform of the Miégebat hydroelectric power station's water chamber via masonry stairs.

(5) From the platform, the view of the penstocks descending into the valley is impressive.
You can climb up to the concrete wall at the end of the underground canal coming from the SNCF/EDF dam in the heart of the mountain.

Immediately behind the platform, take the path that leads south. This is the Sentier des Fenêtres (Window Trail); it is not marked but is wide and in very good condition at the start. On the other bank of the Ossau, you will discover the Gorges du Bitet and the Pic de Bouerzy (1,750 m).

Very quickly, you will come to the first recently installed handrails, then a first window.
This is a gallery carved into the rock, perpendicular to the path. At the end of this 20-metre gallery, there is a closed door that leads directly into the underground canal from Artouste to Miégebat. About thirty minutes after the water chamber, you will reach the first horizontal ladders, which allow you to cross passages where the path is too narrow or non-existent. It's usually quite airy!

(6) From several places, you can see the Crête and Pène de Cézy above your head, an incredible water reservoir that feeds the entire right bank of the Gave d'Ossau. Continue east-southeast until you reach the end of this path, at the junction with the^GR®10, with two clearly visible signposts on a pole.

(7) Take the^GR®10on the right towards the Corniche des Alhas. The path is wide and well marked. It is signposted according to the^GR® codes in red and white. Reach the Torrent du Soussouéou. There is a beautiful waterfall, a concrete footbridge to cross and the SHEM water intake facilities.

(8) You can walk along both banks to explore these technical installations. Cross the footbridge and continue on the^GR®10towards the Corniche des Alhas.

You will reach the so-called vertiginous passages, which are much less vertiginous than those on the Sentier des Fenêtres.
These passages have no horizontal ladders but do have handrails in excellent condition.
The Corniche des Alhas follows the contour line (starting at 1,129 m and ending at 1,100 m) and eventually reaches the Route forestière du Piet track. Follow it to the left for a few dozen metres.

(9) Take the path on the right, which cuts across the track several times. Here, you leave the^GR®10, which continues along the track, climbing to the left. It is better to take the descending path than the supposedly easier option of the track, which also descends.

At a bend at around 920 m, the path meets and merges with the^GR®108. You will (practically) not leave it until you reach the village of Eaux-Chaudes. The red and white markings resume here. This is also a Way of St James, marked with a scallop shell symbol.

(10) At an altitude of 870 m, at a point where the trail crosses a wide bend in the track, it heads towards the Gave d'Ossau river and approaches it, overlooking it. You can see some beautiful pools and waterfalls. Reach a bridge crossing the river.

(11) Do not cross it; turn right instead. Pass between the two buildings and continue on the^GR®108.
This section runs along the banks of the river through a chaos of rocks fallen from the Cézy and a mossy forest. It is very beautiful and relaxing! You will reach the Miégebat power station on the other bank.

(12) Cross a wooden footbridge over the penstocks descending from the balance chimney you passed in the morning. A few hundred metres further on, a metal footbridge allows you to cross to the left bank and reach a large car park and picnic area. This is a tricky section, as you will need to cross and follow the D934 for a few metres before continuing on the path. Take care, especially if you are in a group.

(13) Take a path on the left that climbs above the D 934. At a bend, the path meets the small road leading to the village of Goust. Do not go down to the D 934 to save time!
Turn left onto the road going uphill, which is very beautiful.

(14) Do not enter the hamlet of Goust, but turn right at the hairpin bend onto the track that descends towards the village of Les Eaux-Chaudes. This track is the old tarmac road leading from Les Eaux-Chaudes to Goust. It is sometimes sunken or collapsed.

(15) In the penultimate bend before reaching the D934, turn left into the undergrowth onto a barely visible path leading to the Source du Pont d'Enfer.
Depending on your physical condition:
- either pass the horizontal ladders and the mini-dam of the resurgence to rejoin the path on the other side of the spring (this is the description of this route; difficult and exposed). You will temporarily leave the^GR®108,
- or retrace your steps and reach the hamlet of Pont d'Enfer via the D934, staying on the^GR®108.

(16) Return to the^GR®108, take the lower path, parallel to the river, leading to the Thermes footbridge.

(17) Cross the river and turn right to reach Eaux Chaudes (S/E).

(E)

NB: This hike uses part of the description of the Visorando hike on this site, no. 1105370, by the same author, from the village of Eaux-Chaudes to the Grande Grotte des Eaux-Chaudes. For a complete description of the cave hike, please refer to that hike.

The description is based on a solo hike in spring 2021. The use of a GPS or smartphone with the Visorando app is recommended in addition to the map and this description.

Parking at the start.

Parking is usually available near the Auberge La Caverne. Alternatively, there is also parking in the village of Eaux-Chaudes below the main road D934.

Time indicated:
I completed this route in 6 hours 30 minutes, including breaks and a picnic. This is a fairly short time. Allow between 7 and 7½ hours.

Difficulty:
This hike is classified as difficult due to aerial passages (6), some of which are very high (15), which can be avoided, and the entire unmarked section from (4) to (7).

There are not necessarily handrails in addition to the horizontal ladders used to cross them.
This is a relatively challenging route, reserved for hikers who are not afraid of these difficulties.
The IBP index (automatic route difficulty assessment system), a partner of the FFRandonnée, is 87 HKG, which corresponds to a Difficult route for a hiker with average physical fitness.

Water points:
There are no drinking water points on the route. Springs, lakes, rivers and runoff water are not guaranteed to be drinkable due to grazing livestock. Allow 1.5 litres per person.

Shelter:
In case of emergency, the two caves can be used as temporary shelter. There are no huts or refuges for overnight stays along the route.

Equipment:
Bring the usual equipment for hiking in medium-altitude mountains: hiking boots, suitable clothing, rainwear, sunglasses, water, food, survival blanket, knife, compass, map, whistle, sunscreen, lip balm, walking stick(s) if necessary. A GPS or the Visorando app on your smartphone can complete your equipment to make your hike truly safe.

Traffic:
- In summer, the trail can be quite busy up to the Grotte des Eaux-Chaudes. Beyond that, you will be alone until you reach^{the GR®108}, where you may start to see a few other hikers.
- In winter, when there is snow, you will be alone along the entire route.
Whatever the season, don't forget to tell your friends and family your exact route and inform them of any changes by text message or telephone.

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If you notice any errors in the markings or place names on your route or on the map you are using, you can become a contributor and report them:
- marking errors, safety issues, usage conflicts, environment, etc.: click here
- mapping errors, place names, etc.: click here

On the Sentier des Fenêtres trail (4) at (7), metal collars sealed to the rock supported electrical or telephone cable poles. Only the collars and sealed pitons remain.

Village of Eaux-Chaudes:
The reputation of Eaux-Chaudes is based on more than twelve centuries of history and experience.
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