Depending on what month you roll into CO, a lot of the trails are closed for spring runoff.
If you have never been to Rocky Mountain National Park, I would say it's worth seeing at a minimum ounce in your life. I have taken the wife (hates camping) and x2 5 year olds & 2 years old and had fun seeing the wildlife and going on many short hikes.
The park is right by Estes Park and is not a bad town to explore if you need a recharge from the trail. From Estes I would recomend doing the Peak to Peak Hwy (South) that runs all the way to Golden, CO. There are many trails to go exploring along the Hwy.
An easy trail area with dispersed camping is up by Red Feathers lakes. The area is directly west of Red Feathers Lakes, and there is an old Fire Watch Tower on dead man look out that you can climb to the top if a volunteer is on site. Or you could stay at Red Feather Lakes and go fishing.
If you have never been to Ouray, CO you should go, but I recomend mid to late summer if you want to do all the big name pass trails.
Colorado has a lot to offer, but because you are a single vehicle I would caution you not to push beyond your limits. Things can go wrong very quickly in the back country. If the unfortunate happens, there is a volunteer rescue organization ”Colorado 4x4 Rescue and Recovery” that will recover vehicles from the backcountry if things go wrong and you found your self-stuck.
Hope this helps.
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