(CNN) — Here's a look at Mount St. Helens, the most active volcano in the Cascade Mountains in Washington. Facts: Mount St. Helens is a volcano in the Cascade Mountains, in the area called the Mt. St.

Forty-five years ago on May 18, 1980, Mount St. Helens in the state of Washington violently erupted. Here’s a look at volcanoes, then and now. The 1980 Mount St. Helens eruption began with a steady ...

Forty years ago, a volcano in the Cascade Mountains in Washington roared, expelling plumes of ash and killing 57 people in the most destructive eruption in modern US history. See 50 photos from the ...

When Mount St. Helens erupted on May 18, 1980, it was the most economically destructive volcanic activity in U.S. history. Here are some other interesting facts about the volcano, from the U.S.