Big Bend National Park is the Window Trail.
The park's website says this about the trail:
Difficulty: Moderate; Distance:, 5.6 miles round trip
Begin at the Chisos Basin Trailhead
This trail descends through Oak Creek Canyon to the Window pour-off
which frames panoramic desert vistas. During wetter periods Oak Creek
may be flowing, and must be crossed several times. Use caution on this
trail: the top of the Window pour-off is slickrock with no railings, and
the return hike is uphill.