Located about 12 miles east of Jackson, CA is Indian Grinding Rock State Park. Created in 1968 at elevation 2,400 feet above sea level in the Sierra Nevada foothills, the park contains the largest collection of bedrock mortars in North America. These "holes" which number over a thousand were ground into the marbleized limestone outcropping by Native Americans as they prepared acorns and other food staples.
The park's museum features a variety of exhibits and an outstanding collection of Native Sierra Nevada Indian objects on display including basketry, tools, and other artifacts. Located in the middle of the oak tree dotted valley is a reconstruction of a Miwok Indian village, including a ceremonial roundhouse.
Local foothill tribes represented in the museum are Northern, Central and Southern Miwok, Maidu, Monache, Konkow, Nisenan, Foothill Yokuts, Tubatulabal and Washo.
For more information go to California State Parks