It has been some years, but here is some details pulled out from memory:
We stayed at a campground a little north of Hecho itself. Even from that campground did we have good observations of vultures. Going on the paved road north from Hecho will take you to the infinierno del diablo (or something similar, where the road and the river come very close). This seemingly used to be a breeding spot for wallcreeper, but you are probably too late in the year for finding it here, just as we were. Beyond that spot is the higher valley, with a monestary of some type from where the trail goes into some interesting areas (sorry, I am vague on the details there).
Around Torla, we stayed at the campground just N of town that sprawls up to the left of the road. From the campground we could look across the valley at a big rock with Chough, Peregrine, vultures, and short toed eagle observed from right there. Continuing up the valley, the entry for Parque National the Ordesa is on your right: we could not enter due to having a dog with us, but that is famous for its birdlife. What we did instead was to take the left turn (a really low vehicle might have a problem with one of the dips on this unpaved road? - we drove a regular hatchback), and go to the end where the roman bridge is the start of a trail going up towards the French border. I remember seeing Golden Eagle in that area. Driving south of Torla and going east, you will after a while get to a small paved road going back towards Torla that is passing through a fantastic gorge (this was a one-direction road when I visited). There were breeding vultures on the cliffs along this road and the scenery is fantastic. I think it was where that road ended that a trail goes into another part of the PN, again with good raptor views.
I wish I was going back, thinking of all this!
Niels