Lava Beds National Park, CA

Lava Beds National Monument is located in northeastern California, in Siskiyou and Modoc counties. The monument lies on the northeastern flank of Medicine Lake Volcano and has the largest total area covered by a volcano in the Cascade Range. The region in and around Lava Beds National Monument lies at the junction of the Sierra-Klamath, Cascade, and the Great Basin physiographic provinces. The monument was established as a United States National Monument on November 21, 1925, and includes more than 46,000 acres (190 km²).