FLAGSTAFF — Did you know Flagstaff is home to one of the largest lava tube caves in the country? The Lava River Cave in the ... still exist here in northern Arizona to this day," said Shaffer.

Lava River Cave is located almost 20 miles northwest of downtown Flagstaff off of U.S. Route 180. Visiting is free. Although the cave is open year-round, roads may close in winter, particularly in ...