ALSO SEE | Washington state's volcanoes ranked among nation's most hazardous With researchers monitoring Mount Rainier so closely, Iezzi said if a big eruption were to occur, it’s likely "we ...

An active stratovolcano, Mount Rainier's last significant eruption was around 1,000 years ago. (There was some unconfirmed minor activity in the 19th century.) Although it hasn’t erupted for a ...

One of the world’s oldest national parks, Mount Rainier became part of the federal system in 1899, shortly after its last eruption. Park status was the culmination of a long campaign by John ...