Flattop Mountain is a 23.48-mile out-and-back foot trail in Glacier National Park, Montana. It climbs 3,606 ft to a high point of 6,864 ft. Difficulty: very strenuous, from the NPS hiking-rating formula.
Open Flattop Mountain on Trailbound's interactive map to see the full route, the elevation profile, today's forecast and any park alerts for Glacier. Glacier has permits or reservations for some areas: see the Glacier page for what's needed.