06/2013 | Bill Williams Mountains (foreground), northern Arizona. The Pliocene Bill Williams Mountain volcanic complex comprises a suite of coalescing andesitic to dacitic lava flows and volcanic domes emplaced about 3.5 million years ago on the southwestern edge of the San Francisco volcanic field, east of Flagstaff, Arizona. The town of Williams is left of BWM. On the horizon, from right to left, are four younger volcanic vents: Mount Elden, the San Francisco Peaks (including Humphreys Peak the highest point in Arizona at 12,637’), Kendrick Peak and Sitgreaves Mountain.
Newhall, Wolfe and Ulrich, 1987, "Geologic Map of the Southwest Part of the San Francisco Volcanic Field, North-Central Arizona." https://ngmdb.usgs.gov/Prodesc/proddesc_5528.htm