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How dangerous is Mount Rainier?

Although Mount Rainier has not produced a significant eruption in the past 500 years, it is potentially the most dangerous volcano in the Cascade Range because of its great height, frequent earthquakes, active hydrothermal system, and extensive glacier mantle.

Mount Rainier has 25 major glaciers containing more than five times as much snow and ice as all the other Cascade volcanoes combined. If only a small part of this ice were melted by volcanic activity, it would yield enough water to trigger enormous lahars (debris flows and mudflows that originate on a volcano). Mount Rainier's potential for generating destructive mudflows is enhanced by its great height above surrounding valleys.

Learn more: USGS Cascades Volcano Observatory