You've done such a wonderful job of creating depth and shadow, it all looks realistic. The river sells this. It looks real, with all the intricacies of a real water source. The main river meets up with a tributary on the bottom left, and a smaller river coming from the middle ground temple, with high flow area's and calmer flowing area's. I've seen a lot of other mattes, and they didn't hold up because of the water in their scene being blurry and highly erased. I can't tell at all where something blends in with another. I love that.
The buildings all hold up. They are all lit from the same source. I like how the temple closest to the viewer, the one with the calm river running from it, is lightly turned from the others perspective, so it doesn't have such a strong source on the eastern side of it. Nice touch. And my favorite part of this one is one of the smallest details; the pathway's on the hills. I'm not sure what they are, but they just look like they belong.
Amazing. Amazing amazing amazing.
I was almost sure it was a picture you took while it was still there!