Bill Williams Mountain is a mountain and lava dome volcano in northern Arizona within the Kaibab National Forest. About 31 miles west of Flagstaff and 3.5 miles south of Williams, it is part of the San Francisco volcanic field, one of the peaks formed by the region’s volcanic history. The mountain takes its name from Old Bill Williams, a 19th-century scout, guide, and mountain man. Its significance joins those two histories: the frontier-era figure for whom it was named and the volcanic landscape that shaped the area around Flagstaff.