The highest mountain in the Cascade Range, Mount Rainier is a stratovolcano in the US state of Washington with a summit elevation of 4,392 m (14,409 ft). It is an active volcano which last erupted between 1820 and 1854, and is one of 16 listed Decade Volcanoes across the world – those which, if they were to erupt, would likely cause the greatest loss of life and damage to property.
Mount Rainier is heavily glaciated, its summit topped with 26 majors glaciers and extensive snowfields, although the two craters on its summit are free from snow and ice due to the volcano’s geothermal heat. Within these craters hide the world’s largest volcanic glacier cave network, covering nearly 3.2 km (2 mi) of passages. These caves are the only way to access the highest crater lake in North America, with a surface elevation of 4,329 m (14,203 ft).
Between 8,000 and 13,000 people attempt to climb the peak every year. But it is not an easy climb: only around half of such attempts are successful. Conditions are difficult due to the huge glaciers, unpredictable weather, rock and ice fall and avalanches.
But the lower areas of the mountain are highly popular with visitors, especially hikers. Below its iced peaks, the mountain slopes are covered with old and new growth forest, lakes, waterfalls and river valleys formed by run-off water from glaciers. Marmots, coyotes, elk, deer and black bears roam the mountainside, as well as a rich variety of birdlife.
There are guided tours or you can explore solo. A wide range of winter sports are available including backcountry skiing, cross-country skiing and snowshoeing. The mountain offers something for everyone.
Although there have been no signs of volcanic activity since 1894, it’s thought that if Mount Rainier erupts again, it could cause huge lahars to swamp the whole Puyallup River Valley, adversely and seriously affecting its 150,000 inhabitants.