The Hazel-Atlas mine in Antioch, a dormant operation that extracted coal and silica from the foothills of Mount Diablo, has tours available.
If you go
- Where: Black Diamond Mines Regional Preserve, 5175 Somersville Road, Antioch
- Hours: Visitors center open 10 a.m. to 4:30 p.m. on weekends from March through November; mine tours require reservations; call 510-544-2750
- Cost: Tours are $5; parking is $5
- More information: ebparks.org/parks/black — diamond.