Hi, Tyrrek,
Your comment reminded me of something I heard long ago, and I just have no way of knowing if it was true or a story.
I have heard that the designation of "coto privado de caza" (which, as Tyrrek says, is very prevalent in all sorts of terrain along all sorts of Caminos) is used by the landowners as a way to prevent "the public" from acquiring a right to walk over private land. That is, that if your land is designated as hunting grounds, the public will never acquire a right of way across it, presumably because you were first to reserve your right to shoot all around on it. Conversely, if you leave your land open and unmarked, then the public can, after the requisite number of years of open notorious usage, acquire the right to walk across your property. What this person told me was that in the vast majority of cases, no hunting ever takes place on these "cotos privados de caza", but that it serves only the purpose I described as defeating the public right of way.
Does anyone know whether this is true? So much of my knowledge of Spain comes from what ordinary people tell me on the villages along the way, and I rarely have any ability to know if it´s true or false!
Buen camino, Laurie