What three states are covered by the volcano range including the North Cascades?
Cascades Volcano Observatory The David A. Johnston Cascades Volcano Observatory is the volcano observatory that monitors volcanoes in the northern Cascade Range. Its territory covers Oregon, Washington, and Idaho. The Cascade range's southernmost reaches extend into Northern California, and Cascade volcanoes south of the Oregon-California border—such as Mt. Shasta—previously fell into CVO's jurisdiction. However, as of February 2012, these volcanoes fall under the jurisdiction of the newly formed California Volcano Observatory (CalVO), based in Menlo Park, CA which monitors and researches volcanic activity throughout California and Nevada.
Entiat Mountains The Entiat Mountains, or Entiat Range is a mountain range in the U.S. state of Washington. Located west of the Columbia River, north of the Wenatchee River, and south of the Entiat River, the range is part of the North Cascades section of the Cascade Range. The Entiat Range is relatively narrow east to west and long north to south. The Entiat River valley separates the Entiat Mountains from the Chelan Mountains to the northeast. To the west and south, across the Wenatchee River and tributaries such as the Chiwawa River are the Wenatchee Mountains.