Mount Rainier is an active stratovolcano in Washington, United States. It is the highest mountain of the Cascade Range with a height of 14,411 feet (4,392 m). It's last eruption was around 1827-1894. This high mountain peak was classified as one of the Decade Volcanoes. Since the volcano is so large in glaciers, if the volcano erupts like Mount Saint Helens, it would be much bigger and would probably have a level 6 eruption.