Upper Lost Lake Trail is a 3.5-mile out-and-back foot trail in Rocky Mountain National Park, Colorado. It climbs 545 ft to a high point of 10,693 ft. Difficulty: moderate, from the NPS hiking-rating formula.
Open Upper Lost Lake Trail 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.