However, ask a volcanologist where the real risk in the U.S. lurks, and there’s a good chance that they will turn their gaze to the Pacific Northwest.

Nestled among the Cascade mountain range sits Mount Rainier, a postcard-perfect natural wonder—and a volcano that causes scientists genuine concern. It’s unclear when it will stir from its long slumber, and there’s no sign that anything is imminent. Nevertheless, a future eruption could cause one of the worst natural disasters in the U.S. (See pictures of the 10 most dangerous volcanoes in the U.S.)