Mount Rainier is the most glaciated peak in the contiguous United States.
Mount Rainier is an active stratovolcano in Washington’s Cascade Range. It rises to 4,392 metres and supports extensive glaciers, including Emmons Glacier, the largest glacier by area in the contiguous United States. Snow and ice cover its summit and upper slopes throughout the year.
Rainier is also a major hazard because its steep volcanic slopes hold large amounts of ice and unstable rock. If heated by an eruption or destabilized by collapse, this material could generate lahars, fast-moving volcanic mudflows that threaten valleys below.
The mountain is protected within Mount Rainier National Park, established in 1899. Its glaciation and prominent profile make it one of the best-known volcanoes in the Cascade Range.