I’ve been to Colorado backpacking in Rocky Mountain National Park near Estus Park. We took the Thunder Lake trail over the continental divide. It was AWESOME! the trail is pretty hard though, if some of the people with you havent hiked before you might want to rethink this trail, from 2 miles to the divide, up over, and a mile past there is no trail, so you’ll need a topographic map and compass for sure. Good luck!
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