Mount Hood is Oregon’s highest mountain, an active stratovolcano in the Cascade Range shaped by glaciers, lava domes, and continuing geothermal activity. The U.S. Geological Survey considers it potentially active and the state’s most likely volcano to erupt, with at least four major eruptive periods in the last 15,000 years, the most recent in 1781 to 1782. Named in 1792 by Lieutenant William Broughton, it later became a prominent landmark for Lewis and Clark. Today it is both a significant volcanic hazard and one of the Northwest’s best-known recreation mountains, with climbing, ski areas, Timberline Lodge, and extensive trails in the surrounding national forest.