South Rim is a roughly 12.6-mile out-and-back foot trail in Big Bend National Park, Texas. Difficulty: strenuous, from Trailbound's popular-hike list. That is the full hike: the mapped trail line covers only 4.02 mi of it, so don't plan from the map line alone.
Open South Rim on Trailbound's interactive map to see the full route, the elevation profile, today's forecast and any park alerts for Big Bend. Big Bend has permits or reservations for some areas: see the Big Bend page for what's needed.