Box Canyon in Ouray County, Colorado, figured in the early history of Ouray when a mining camp in the canyon helped the settlement become a permanent community in the San Juan Mountains. It is most famous for Box Canyon Falls, where water plunges 285 feet between steep quartzite walls that extend nearly 100 feet farther and create the gorge’s enclosed form. The canyon also preserves an angular unconformity, where the Elbert Formation lies atop the much older Uncompahgre Formation, revealing a gap of about 1.3 billion years in geologic time. Today it is prized for both dramatic scenery and deep geologic history.