There is a "chute" from the back door of the arena to this back paddock so he can run in and out. There is planty of mud, a drainage ditch, and a pile of topsoil (which he climbs) so he is getting used to handling himself as well as getting used to stepping in "yucky" stuff.
He goes out there half the day by himself. He is only about 15 feet from the outdoor arena which serves as the sacrifice pen for Mom's two geldings. But, he doesn't hang on the fence at all, and seems to barely notice the others are out there. He is very independent and is still simply thrilled at his new found freedom.