Snow-mantled Sunset Crater (left-center), seen from O'Leary Peak to the NW, is the youngest volcanic feature of the San Francisco Mountain volcanic field, which covers a vast area of northern Arizona between Flagstaff and the Grand Canyon. The Sunset Crater eruption began about 1100 CE from a chain of cinder cones and vents trending NW-SE, the largest of which is Sunset Crater. Three lava flows were erupted, the longest of which traveled 11 km to the NE.

Photo by Ed Wolfe, 1973 (U.S. Geological Survey).

This image is made available as a Public Domain Work, but proper attribution is appreciated.

San Francisco Volcanic Field