PHOTOS: May 18 marks 42 years since Mount St. Helens eruption

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In 1980, a major volcanic eruption occurred at Mount St. Helens, a volcano located in state of Washington, in the United States.. (Photo by: Photo12/Universal Images Group via Getty Images)

Forty-two years ago, Mount St. Helens in southwest Washington state erupted, killing 57 people. The blast sent more than 1,300 feet off the top and raining volcanic ash for miles around.

Within minutes of a 5.1 earthquake that hit at 8:32 a.m. on May 18, 1980, the volcano’s north flank collapsed, triggering the largest landslide in recorded history.

That set off powerful explosions that sent ash, steam, rocks and volcanic gas upward and outward.

The lateral blast scorched and flattened about 230 square miles of dense forest.

Soon after, a plume of volcanic ash rose over 80,000 feet and rained down as far as 250 miles away in Spokane.

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Pushed by winds over the next few days, the ash cloud traveled east across the U.S. and encircled the globe in 15 days.

The eruption blew about 1,314 feet off the volcano and created a horseshoe-shaped crater in the mountain, which now stands at 8,363 feet.

Today, the volcano has become a world-class outdoor laboratory for the study of volcanoes, ecosystems and forestry, as well as a major recreational and tourist destination.