Mount St. Helens is an active stratovolcano located in the state of Washington. It is famous for its catastrophic eruption on May 18, 1980, which significantly altered the landscape and had a profound impact on the surrounding environment. The eruption was the deadliest and most economically destructive volcanic event in U.S. history, resulting in the loss of 57 lives and extensive damage to property. Today, Mount St. Helens is a popular destination for visitors interested in geology and natural history. The area around the volcano has been designated as the Mount St. Helens National Volcanic Monument, allowing for research and education about volcanic activity and ecosystem recovery following the eruption.