North Boundary, Upper is a 11.42-mile out-and-back foot trail in Rocky Mountain National Park, Colorado. It climbs 2,452 ft to a high point of 9,720 ft. Difficulty: very strenuous, from the NPS hiking-rating formula.
Open North Boundary, Upper on Trailbound's interactive map to see the full route, the elevation profile, today's forecast and any park alerts for Rocky Mountain. Rocky Mountain has permits or reservations for some areas: see the Rocky Mountain page for what's needed.