The peak Llana del Bozo is the western summit of the trilogy of Aisa both with Llana de la Garganta and Aspe. It’s a high and nice peak with two main routes, one from Refugio de Lizara (West) and another one from Rigüelo (South East), the same trailhead of normal route of Aspe. In spring or summer is an easy climb but in winter the climb is harder and it’s necessary a little of experience in the use of crampons and ice-axe.
The normal route is from Aisa following the road to Rigüelo at North of the village. From this side the peak is accesible across the col East, the Brecha Wallon between Llana del Bozo (2.559m) and Llana de la Garganta (2.597m).
Another option is the route from the mountain hut of Lizara crossing col del Bozo to the valley of Rigüelo. In this case the access is from the NW face using a col between Sierra de Bernera and Llana del Bozo.
In the road between Jaca and Canfranc see the deviation to left indicated as Borau / Aisa before Villanua.
Another possibility to Aísa: It is not properly indicated by road signs, but if you bother to ask people in Jaca they might tell you about another road to Aísa. It starts from the farther end of the gardens placed by the Gran Hotel, and offers a little better road (road design and floor quality) to get to Aísa, even if a little longer.
Start from Huesca or Pamplona, in northern Spain. From any one of both towns, follow road N-240 towards the other one. At Puente la Reina (88 km away from Pamplona, or 72 km away from Huesca) you will have to turn north by road A176. This is the road running alongside the river Aragón Subordán, entering the Valley of Hecho. After 16 km, turn right once again to take road HU212 into the valley of Aragüés. This is narrow but good road taking you to the village of Aragüés del Puerto. 7 km after the village you will find the Restaurant "Los Corralones" (in a beautiful pine forest), and 3 km farther the parking of the Lizara Mountain Hut, at the base of Bisaurín.
Red TapeThe roads of Aisa-Rigüelo or Aragües-Lizara are generally closed in winter of after a recent snowfall.
External Linksmendikat.net: text in Spanish.
Fidel Mendia: alternative route across a couluoir (it's not the normal route).
osakimendi: images of normal route.