Back to the OP, there is a pantomime horse. Really. It was used for the extreme distant shots of the Fellowship up in high places (like that shot of the hill with the ruins on it) and in some of the swamp scenes when the horse was really in the thicker parts of the mud - but all you can see is the head in shot, so it’s not easy to pick. Deliberately framed to hide the fact that it’s a fake horse, of course. Of course.