I live in Estes Park, and there is a couple good places up here, not real technical but alot of fun. Let me know if you want to go sometime. There is also some nasty stuff about 20 miles from here, but It gets crowded and people tear the hell out of it. Plus I still have open diffs. Jesse.
We did a lot of 4 wheeling up by Central City. You can take a number of roads that go from Central City over the mountain to the Fall River Road. I'm pretty sure they renamed this road and it is now the Alice/ St. Mary's Glaicer exit off I-70. This exit is just west of Idaho Springs. There are some challenges in there if you drive around enough. For the most part, it's pretty moderate. It's a great place to cut your teeth and see what you machine can do. Many good times up there.