The Cascades

The Cascades are a magmatic arc that extends from southwest British Columbia to Northern California and includes more than 2,300 Quaternary volcanoes. Fewer than 30 of the 2,300 are the high peaks that provide the popular image of a Cascade volcano. Of these, we closely monitor about 13 U.S. Cascade volcanoes, including those identified by the framework for a National Volcano Early Warning System (NVEWS) as very high threat and high threat.

Cascade Volcanoes