I recently found this website called fragarmor.org. It was a little group that used to have remote controlled allied/axis tanks and had a little fun with them on a patch of land. I do not know if they still use that land for this anymore, considering there is no update of pictures for 2006, but i may be wrong. It has pictures that seem interesting and many if you are interested in RC tanks, and the location is in denver, I suggest checking out the site before joining as it says something about a $50 yearly fee.
Edit: They still have that land and it is in continued use of RC tanks of WWII use.