Grizzly Mountain, Mountain summit in Crook County, Oregon, US.

Grizzly Mountain is a summit in Crook County that reaches approximately 5,629 feet above sea level. The peak displays steep slopes formed from welded volcanic material and supports pine and juniper growth on its northern side.

The mountain developed through volcanic activity linked to the formation of the Crooked River Caldera, leaving behind layers of compacted ash. This geological process created the rocky character visible on the slopes today.

Grizzly Mountain is a welded tuff peak in the Crooked River caldera, and its name ties it to the grizzly bears that once ranged this part of Crook County. The summit is a local landmark above Prineville, and the mountain's rocky slopes are part of the caldera's volcanic record.

The mountain can be reached via a road on the southeast side, though the final climb involves sections with loose rock that require caution. Visitors should be prepared for uneven terrain and exposed areas.

Grizzly Mountain is a piece of the Crooked River caldera: its rock is welded tuff, ash compacted by heat after a massive eruption. The summit stands at 5,629 feet (1,716 m), about 1,715.74 m in metric surveys, near Prineville in Crook County.