Alternative route avoiding motorway. A bit of everything on this route, some faster sweeping roads out some more twisty ones, my personal favourite part is from Yesa and the N-260 up into the mountains and all the way to Ainsa. Approximately 6 hours! Depending on how many times you stop to admire the scenery.
Good cross country route from the Picos de Europa to the Pyrenees, 1st half Twisty/Scenic, 2nd half faster more direct