Here's another shot, with different horses/horse groupings:
http://www.telegraph.co.uk/news/picturegalleries/picturesoftheday/8864437/Pictures-of-the-day-2-November-2011.html?image=7. There is also a third view during snowy weather, but I didn't save that link.
I researched it quite a bit to see if it was photo shopped, and to find the source. I
think it is a real structure. A couple posters say that a German
wood designer, Jens Braun, built it. I think it's likely that he built it as a piece of
art that had nothing to do with any permit, but the photo was tagged that way by someone. If someone can search in Deutsch, perhaps we'd get the real scoop.