Four of us took BART out to the end of the line and then biked to Black Diamond Mines Regional Park in Antioch for a tour of the Hazel-Atlas sand mines (and some history on coal mining in the region).
It was a casual 20 mile round trip, mostly on the Delta De Anza paved off-road bike path, though with a bit of busy road riding and then a mile of uphill to get into the park.
This was one of the better historical tours I’ve taken, and I highly recommend it– our guide (Philip?) was entertaining, kept a slide show interesting, and we got to walk down into the cool dark mine. Some maps and photos…
The view descending back out of the park:
A railroad to nowhere?
Visitor center (I want to find one of these mason jars):
Slideshow:
Tour down into the mine:
Massive stopes above and below where we walked (low-light cell phone photos can’t do the experience justice, of course):
Safety first:
Another fine afternoon.