Mt. Shasta last erupted in 1786, and the French explorer La Pérouse witnessed it from his ship. The highest cone of the mountain, Hotlum Cone, has erupted at least eight times during the past 8,000 years. It is located in Siskiyou County, California.
Mount Shasta's three possible previous eruption dates include 1250, 1200 and 850. It rises 10,000 feet above the surrounding landscape, and its estimated volume of 84 cubic miles makes it the most voluminous volcano in the Cascade Volcanic Arc.
A giant landslide swept away its entire northern side approximately 300,000 to 360,000 years ago. The landslide, with a volume of 1.6 cubic miles, is one of the largest on Earth.