Around AD 1064 a cinder cone erupted on this spot, spewing ash across 800 sq miles, spawning the Kana-A lava flow. Now the 8029ft Sunset Crater is quiet, and short trails wind through the Bonito lava flow (formed c 1180) and up Lenox Crater (7024ft). More ambitious hikers and bikers can ascend O'Leary Peak (8965ft; 8-mile round trip), or there's a gentle, 0.3-mile, wheelchair-accessible loop overlooking the petrified flow.
Sunset Crater is 19 miles northeast of Flagstaff. Access fees include entry to nearby Wupatki National Monument, and are valid for seven days.