Sourdough Falls Trail Lower Loop is a 0.68-mile out-and-back foot trail in North Cascades National Park, Washington. It climbs 30 ft to a high point of 1,508 ft. Difficulty: easy, from the NPS hiking-rating formula.
Open Sourdough Falls Trail Lower Loop on Trailbound's interactive map to see the full route, the elevation profile, today's forecast and any park alerts for North Cascades. North Cascades has permits or reservations for some areas: see the North Cascades page for what's needed.