I've followed Kien Do's trail and gotten to where the tree stands are in the small valley. I've been able to kill everyone but can not figure out where to climb up, even using my senses. I can see where the farthest tree stand is with a path out and a line across, and I can navigate some of the walls. Any hints?

i am in the same exact position... after u kill all the guys where am i supposed to climb up i feel like breaking this game in half because some parts like this are just retarted someone if you how to get through this help us

check out the trees in the back of the valley, there are 3 together with a platform with part of a plane hanging off. the front tree on the rightish side you can climb up. same place you saw on of the others go up in the video just before the last fight.