Indian Grinding Rock State Historic Park nestles in a little valley 2,400 feet above sea level with open meadows and large valley oaks that once provided the native Americans of this area with an ample supply of acorns. The park was created in 1968 and preserves a great outcropping of marbleized limestone with some 1,185 mortar holes—the largest collection of bedrock mortars in North America. The Museum has been designed to reflect the architecture of the traditional roundhouse. Exhibited in this two-story museum are outstanding examples of the technology and crafts of the Miwok and other Sierra Nevada native American groups.

The park offers exhibits, tours, educational programs, and occasional recreational and educational events.