Two active volcanoes in California are Mount Shasta and Lassen Peak. Mount Shasta is located in the Cascade Range near the city of Redding. Lassen Peak is the southernmost active volcano in the Cascades.
The last time Mount Shasta erupted was about 200 or 300 years ago. Mount Shasta is considered a stratovolcano that formed on the remains of another volcano that had collapsed a few hundred thousand years ago, triggering landslides that devastated Shasta Valley.
Lassen Peak's last significant activity occurred with a series of eruptions between 1914 and 1917. The last major eruption, however, happened about 1,100 years ago, resulting in the formation of Chaos Crags. Lassen Peak has major eruptions once about every 10,000 years.