page_title: Mount St. Helens
section_title: History
hierarchical_section_title: Mount St. Helens / History
context_page_description: Mount St. Helens is a volcano in the U.S. state of Washington. It is 96 miles south of Seattle and 53 miles northeast of Portland, Oregon. The volcano is in Cascade Range of mountains. It is part of the Cascade Volcanic Arc in the Pacific Ring of Fire that includes over 160 active volcanos. This is a deadly volcano.
  Mount St. Helens was first called Louwala-Clough, which means "smoking" or "fire mountain" in the language of the Native American Klickitat people. This volcano is well known for its explosions and flows of lava. Its most famous volcanic eruption was on May 18, 1980. In 1982, U.S. President Ronald Reagan and the United States Congress made the Mount St. Helens National Volcanic Monument, a 110,000 acre area around the volcano that is also a part of the Gifford Pinchot National Forest.
  The 1980 eruption was the deadliest and most economically destructive volcanic event in the history of the United States. 57 people were killed; 250 homes, 47 bridges, 15 miles of railways, and 185 miles of highway were destroyed. A massive debris avalanche was triggered by an earthquake measuring 5.1 on the Richter scale.
context_section_description: Before the eruption in 1980, Mount St. Helens was the fifth-highest peak in Washington State. The peak rose more than 5,000 feet (1,525 m) above its base, where it rises from the ridges that are around it. It stood out from the surrounding hills because of the symmetrical cone shape and the snow that covered the top. Because of its cone-shape, it was called the "Mount Fuji of America", after the famous Mount Fuji which is a symbol of Japan.
caption: Plate tectonics of the Cascade Range. The Cascade volcanoes formed as a result of the Juan de Fuca plate subducting (moving under) the North American plate.