Mount St. Helens had been quiet for 123 years. Then, on March 20, 1980, a magnitude 4.2 earthquake signaled awakening. Over the following weeks, hundreds of earthquakes shook the mountain. A bulge appeared on the north face, growing five feet per day as magma pushed upward. Steam vented from the summit. Authorities established a 'red zone' around the mountain, though pressure from timber companies and property owners kept it smaller than scientists wanted. Geologists monitored constantly, knowing an eruption was coming but unable to predict exactly when. Some people left. Others, like Harry Truman and his sixteen cats at Spirit Lake Lodge, refused.

The end came suddenly. At 8:32 AM on Sunday, May 18, an earthquake destabilized the bulging north face. The entire mountainside collapsed in a landslide that traveled at 150 miles per hour. The exposed magma chamber decompressed explosively, releasing a lateral blast that overtook the sliding debris. The blast cloud - 680°F gases and pulverized rock - flattened 4 billion board feet of timber. Trees up to four miles away were blown down instantaneously. A pyroclastic flow raced down the mountain. Lahars - volcanic mudflows - surged down river valleys. The vertical eruption column rose 80,000 feet in fifteen minutes, dropping ash across eleven states.

Fifty-seven people died in the eruption. David Johnston, a USGS volcanologist manning an observation post six miles north, was killed by the lateral blast - his body was never found. Harry Truman, 83, who had run Spirit Lake Lodge for 52 years and became a folk hero for refusing to evacuate, was buried under hundreds of feet of debris. Photographers, loggers, campers, and curious visitors who had evaded checkpoints or been caught in the expanded danger zone perished. Most died from asphyxiation as ash filled their lungs. Some were found miles from where they'd been standing, carried by the blast. The death toll would have been far higher on a weekday, when logging crews would have been working.

The devastation seemed total. Spirit Lake was gone - buried under debris, reformed as a new lake at a higher elevation, its water acidic and clogged with floating logs. The forests were flattened. The rivers ran gray with sediment. But life returned faster than expected. Within weeks, plants sprouted from the ash. Pocket gophers survived underground and aerated the buried soil. Elk found patches of surviving vegetation. By the 1990s, the blast zone was regenerating naturally - a process that continues today, monitored by scientists studying how ecosystems recover from catastrophic disturbance. The eruption became a laboratory for understanding volcanic hazards and ecological resilience.

Mount St. Helens National Volcanic Monument preserves 110,000 acres of the blast zone. The Johnston Ridge Observatory, five miles from the crater, offers dramatic views and exhibits about the eruption and its aftermath. The windy Ridge viewpoint looks down on Spirit Lake and its floating log mat. Coldwater Lake, formed when the debris dam blocked a valley, offers trails through recovering forest. For adventurous visitors, climbing to the crater rim is permitted with permits (required May-October). The monument is accessible via State Route 504 from Castle Rock, Washington. Portland International Airport (PDX) is 100 miles south; Seattle-Tacoma International Airport (SEA) is 150 miles north. Visiting during clear weather is essential - the mountain is often shrouded in clouds. The landscape remains scarred and beautiful, a reminder of nature's power.