If you can understand Spanish you can look at this site www.picoseuropa.net and its forum www.foropicos.net.
It's full of information on routes and also updated news on weather.

Enjoy

Luis

I recommend you this book:
http://www.libreriadesnivel.com/fichalibro.php?id=7662
and those maps:
http://www.libreriadesnivel.com/fichamapa.php?id=1289
http://www.libreriadesnivel.com/fichamapa.php?id=1288
There are lot of posibilities. If it's the first time that you visit
Picos de Europa, a good option will be going to Vega de Urriello (Delgado
Ubeda) hut (guarded) from Puente Poncebos the first day, passing the remote
village of Bulnes. The next day you can cross to J.R.Lueje hut (Cabrones)
hut and climb Torre Cerredo (2.648 m.), the highest summit in Picos de
Europa and Cordillera Cantábrica range, and sleep in one of those huts. The
third day you can cross to Collado Jermoso hut, passing Cabaña Verónica hut
(not good to sleep: it's very small). The fourth day you can descend to the
villages of Cordiñanes and Posada de Valdeón and return.
To get to Puente Poncebos, you have to go to Arenas de Cabrales
(Asturias). I supose that there are buses from Oviedo. To return from
Posada de Valdeón, I think that there is a bus from León, but I'm not sure.
Be careful in those mountains: the fog is very dangerous. A GPS is very
advisable and good maps (1:25.000)