- Mount St. Helens (Wikivoyage)
Mount St. Helens National Volcanic Monument is a United States national monument in southwest Washington State that was the site of a massive volcanic eruption on 18 May 1980. In 1982, the President and Congress created the 110,000-acre (445-km²) National Volcanic Monument, within the Gifford Pinchot National Forest, for research, recreation, and education.