Mount St. Helens

The site of the most recent and most catastrophic 1980 volcanic eruption on the U.S. mainland, Mount St. Helens is still active. Occasionally rocked by earthquakes, spewing ash, smoke, and steam, and swelling with magma, Mount St. Helens is still a destination for many outdoorsy tourists. Hiking trails are accessible to everyone but if you'd like to make the journey to the crater's rim, you'll need a permit.