Answer: United States
Notes: Recently, Mount Rainier in Washington, United States, experienced over 300 small earthquakes, marking the most significant seismic activity since 2009, as reported by the United States Geological Survey (USGS). Mount Rainier is the highest mountain in Washington state, standing at 4,392 metres. It covers 260 square kilometers and has the largest single-mountain glacier system in the U.S. outside Alaska. It is an active stratovolcano formed by lava flows that began about one million years ago. Its last eruption occurred around 150 years ago.
