Quiz: Which historical event in 1980 significantly affected the su February 20, 2025 by Gideon Lakewood Which historical event in 1980 significantly affected the surrounding areas of Crater Lake? Discover more about Crater Lake Tours at our home page. A) Eruption of Mount St. Helens B) Creation of Crater Lake National Park C) Establishment of the Oregon Caves National Monument D) Discovery of the Klamath Falls Fossils Submit Answer