Mount St. Helens erupted in 1980, in one of the most significant volcanic events in U.S. history.

The eruption, which occurred on May 18, 1980, was a violent explosive event that dramatically altered the landscape of the surrounding area. It reduced the height of the mountain by over 1,300 feet and created a large crater. The eruption also caused widespread devastation, including pyroclastic flows, mudslides, and ash fall, and led to the loss of 57 lives. Today, the area around Mount St. Helens is part of the Mount St. Helens National Volcanic Monument, where visitors can learn about the eruption and its lasting environmental impact.