ROAD ACCESS: From Huesca, take road N240 to Barbastro (49 km then road C1311 northwards (9 km) until you find a crossing and follow the signals to El Grado. Turn left there and enter road C138, which will take you after 59 km to Aínsa (via El Grado and puerto de El Pino). There will be only 39 km left then, first by driving northwards on road HU640 (across Labuerda and Escalona) and turning right after Salinas for a final 13 km drive to Plan. This is a rather narrow road, try not to take in the dark and driving will be much more enjoyable (apart from the great views!). After Plan, the final approach to Biadós Hut takes a further 3 km by road and 10 km more of a not too good dirt road. When you reach the final fork of this dirt road, turn right for Biadós.
For a climb from the french side of the border, the only available road approach begins at the road linking Arreau and Bagnéres de Luchon (via Loudenvielle and Col de Peyresourde). There is a road starting somewhere around Loudenvielle and running south, following the Valley of the Neste de Louron. The end of this road is placed at the north side of Bachimala at Pont du Prat, (about 1250 m high).
TRAIL : From mountain hut of Biadós (1745m) take a good trail surrounding the Barranco de la Rivereta on the right. At the begnning the trail is very large and easy. In the Punta de Leners takes for the right and you'll see the Ibons or little lakes (Millares and Leners) on the right. Continue to Col de Eriste (2890m).From this pass descend about 100 meters, then take the steep slopes on the left without losing altitude. You'll reach a large plateau at 2900 meters, go the well-marked pass between Tucon Royo and Las Espadas at about 3100 meters. This is the real start of the climb, pretty long approach which to my mind deserves one day. It seems difficult to make both the approach and the route in one single day.
The (long) route of Posets through Espadas ridge offers beautiful landscapes from the ridge itself on the rest of Pyrenees.
From the pass just follow the ridge, generally wide and not too steep, to Las Espadas and top of Posets. There is one descent after Las Espadas and 2 "difficult" steps (grade III with french quotation) that could require a rope for unexperimented mountaineers, the first one approximatively 100 meters before Las Espadas and the second one just after the pass at 3200 meters between Las Espadas and top of Posets. The last one can be pretty impressive given that the step surrounds some void on the northern side above the glacier.
For descending from the top of the Posets use the routes described on the "Biados" route
In the early season (late june to early august), depending on the previous winter, it's useful to take an ice axe. Crampons are useless in summer conditions.
Regarding rock climbin gear, to my mind there is no need to take any particular stuff. In case of unexperienced people, you can bring a rope in order to secure the 2 "difficult" steps.
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