Parks & Monuments :: SUNSET CRATER NATIONAL MONUMENT

Sunset Crater is in the eastern part of the San Francisco volcanic field. Sunset Crater is one of the youngest scoria cones in the contiguous United States. It began erupting between the growing seasons of 1064 and 1065 A.D. Eruptions continued in the area for many decades. The cone was named by John Wesley Powell, first director of the U.S. Geological Survey, for the topmost cap of oxidized, red spatter which makes it appear bathed in the light of the sunset. The red, pink, and yellow colors at the top of the cone are silica, gypsum, and iron oxide that formed from fumaroles.

The tremors shook the Earth warning the Sinagua people living nearby. Then, just over nine hundred and thirty years ago, a blink of an eye on the geologic time scale, Sunset Crater Volcano rumbled to life. Fiery lava spewed up from a central vent, drawing molten rock from ten kilometers beneath the surface. Fountains of glowing liquid lava rose hundreds of meters into the air, falling to Earth as cinders.

Remarkably well-preserved evidence of Sunset Crater Volcano’s sudden birth is now protected in the National Monument. Come explore our colorful cinder cone on a virtual field trip. We will take you along a trail that winds across one of the frozen rivers of lava that gushed from Sunset Crater Volcano’s rocky flanks.