Lassen Peak

Lassen Peak, commonly referred to as Mount Lassen, is a lava dome volcano and the southernmost active volcano in the Cascade Range of the Western United States. Located in the Shasta Cascade region of Northern California, it is part of the Cascade Volcanic Arc, which stretches from southwestern British Columbia to northern California. Lassen Peak reaches an elevation of 10,457 ft, standing above the northern Sacramento Valley. It supports many flora and fauna among its diverse habitats, which are subject to frequent snowfall and reach high elevations.

Lassen Peak has a volume of 0.6 cu mi, making it one of the largest lava domes on Earth. The volcano arose from the former northern flank of now-eroded Mount Tehama about 27,000 years ago, from a series of eruptions over the course of a few years. The mountain has been significantly eroded by glaciers over the last 25,000 years, and is now covered in talus deposits.

Source: Wikipedia