Located in the western United States in Washington state, Mount Rainier is the largest volcano in the Cascade Range, reaching a height of 4,392 m (14,410 ft). The majestic volcano is situated near the large urban areas of Tacoma and Seattle. It is one of the most dangerous volcanoes to be located near a huge population and economic center. The main hazard from an eruption of Mount Rainier would be the creation of lahars (landslides or mudflows of volcanic debris that resemble wet concrete). An eruption would probably melt the glaciers capping the mountain, causing flash floods that would mix with loose volcanic ash and other rock debris. This concretelike mixture would rapidly flow down the flanks of the volcano and into the surrounding lowlands, destroying everything in its path. In past eruptions, lahars from Mount Rainier have reached Puget Sound, a large and sheltered arm of the Pacific Ocean that forms the waterfront of several cities, including Seattle. A volcanic eruption of Mount Rainier about 5,700 years ago caused one of the world’s largest-known lahars, and 600 years ago another large lahar was generated on the mountain’s western flank. Even a small eruption of Mount Rainier is almost certain to generate lahars. Today the effects would be devastating to the millions of people who live in the area.