The unvegetated pyroclastic cone in the foreground, seen from near the summit of Prospect Peak, is Cinder Cone in NE Lassen Volcanic National Park. Cinder Cone, which was formed during an eruption several hundred years ago, was the source of an extensive series of lava flows that can be seen on the far side of the cone. The flows dammed up local drainages, forming two lakes, one of which is Snag Lake, seen here SSE of the cone.

Photo by Lee Siebert, 1998 (Smithsonian Institution).

This image is made available under the Public Domain Dedication CC0 license, but proper attribution is appreciated.

Lassen Volcanic Center