Event · Outdoors

Autumn Open House Weekend at Black Diamond Mines

When

Sat, Oct 24 · 10:00 AM

Where

Greathouse Visitor Center, Black Diamond Mines Regional Preserve5175 Somersville Road, Antioch, CA 94509Open in Google Maps ↗

Ages

All ages at the open house; must be 7+ years old to tour the mine; parent participation required

Cost

Free tours; $5 parking fee when kiosk attended

Organizer

East Bay Regional Park District

Upcoming dates: Sat, Oct 24 · Sun, Oct 25

A fall open house weekend at Black Diamond Mines Regional Preserve in Antioch, where visitors learn the stories of the coal and sand miners who lived in these hills and explore the underground workings. Free Coal Mine Experience tours are provided first come, first served (maximum 20 per tour, no advance registration or waitlists); you must be 7 or older to tour the mine, and parent participation is required. The underground Greathouse Visitor Center is open with additional activities for those not touring. Saturday and Sunday, October 24–25, 2026 from 10:00 AM. $5 parking fee when the kiosk is attended. The visitor center is a quarter-mile walk from the upper parking lot with a mild incline.