- California18 objects
- North America18 objects
- The Americas18 objects
- United States18 objects
- CA-CCo-138, Oakley, Contra Costa County16 objects
- Contra Costa County, California16 objects
- Oakley, Contra Costa County, California16 objects
- San Francisco Bay Area, California16 objects
- CA-Sac-2 or 3 or 6 ('Johnson Mound'), Sacramento County, California2 objects
- CA-Sac-6, Sacramento County, California2 objects
- North Central California2 objects
- Northern California2 objects
- Sacramento County, California2 objects