Pinnacle Peak, also called Mount Peak, is a forested extinct cinder cone south of Enumclaw that rises prominently above surrounding farms and lowlands on the western edge of the Cascades. About 5,600 years ago, the Osceola Mudflow from Mount Rainier spread across the flat terrain around it and partly buried the older cone, while basalt outcrops near the summit still show its volcanic origin. The mountain’s name evolved from Mount Pete, honoring early settler Pete Chorak, to Mount Peak through mishearing, and later to Pinnacle Peak after a summit fire lookout. Now part of Pinnacle Peak Park, it is a popular hiking and training destination.