Stewartville, California

Stewartville was an unincorporated place in eastern Contra Costa County, California that is now a ghost town. It was located 6 mi northeast of Mount Diablo, at an elevation of 558 feet (170 m). It was a mining town for the nearby coal mines.

A post office operated at Stewartville from 1882 to 1902. The place was named for William Stewart, coal mine owner.