Cedar Mesa, where Muley Point marks its southernmost tip, was once a fertile highland inhabited by the Ancestral Puebloans, who carved homes from caves and cultivated beans, maize, and squash. As the climate dried and warmed about 800 years ago, they moved away from the plateau. Today, campers and hikers explore remnants of an ancient culture in this stunningly beautiful area.

The cliff’s edge where this photograph was taken is fractured by the alternating freezing and thawing of rain and snow, breaking the surface of the plateau into rectangular blocks. These boulders will eventually fall into the shadowed gorge carved by the San Juan River, a major tributary of the Colorado River.

The San Juan was once a slow, meandering stream crossing a nearly flat delta near sea level. Starting a few million years ago, as this plain rose into a plateau, the river carved deep, becoming entrenched in its original path a half mile below this rim.

Between sunset and twilight, the stark land shifts from dun-colored to iridescent hues of red, magenta, and purple. In the distance, the buttes of Arizona’s Monument Valley contour the far horizon. At this time of day, the brilliant sky and somber land blended into one, creating a rare moment in which I felt untethered from where I stood, like in a dream.