Where to legally ride in Colorado?

I live in Arkansas, and just purchased a nice used RZR 800. I would like to trailer it to somewhere in Colorado and spend a few days (legally) riding easy trails and/or old mining roads. Exploring an old ghost town or mine would be an added bonus. Question: where can I legally ride? What trails and / or roads can I legally ride? What permits (or other) is required?
Ideally, I would like to rent a nice furnished cabin with easy trails near by. Any recommendations?

Also, about 10 years ago, I rented a jeep in Ouray, and we explored old mining roads around the Silverton area… loved it. Now I would like to do the same with my Polaris RZR. Can I legally ride these same mining roads?

Thanks,
Tim