Black Diamond Mines Preserve

Near: Antioch
Distance: 4.5 miles 
Elevation: 300 to 1,200 ft 
Vegetation: Oak and pasture
Last Visit: May 2020

Black Diamond Mines Preserve is another hilly grassy San Francisco East Bay cowpark.  Wide trails climb steep grassy hills with sparse oak trees.  The east-west running ridge running through the middle of the park has a nice combination of views of nearby Mt Diablo to the south, and the flat expanse of the Sacramento River Delta to the north and east.  Sadly my phone was dead on this run so no pictures. Make sure to bring water for yourself and your dog, this route is very exposed with only a few bits of shade up along the ridge.

Rules

Dogs are welcome, but must be on a leash. All else as you'd expect from a standard East Bay cowpark.  Most trails are open to pedestrians, cyclists, and equestrians so keep alert to their passing.

Trailhead

This route starts from an unnamed parking area in the north east corner of the preserve where it adjoins Contra Loma Regional Park.  No facilities or services here, but no fees to park either.

Route

We did this route in the clockwise direction, but I think counter-clockwise will give you more time to appreciate the views sweeping out over the delta to the north and east.  Take the Homestead trail west from the parking area and then the first left to the southeast on the Old Homestead Loop.  This will climb slowly up a valley, then turn right and climb steeply after an intersection with the North Portal trail. When you gain the top of the north-south running ridge, turn left on the Acorn trail to keep climbing to the Ridge Trail on the higher east-west running ridge.  Turn left here  keep on the ridge trail and follow it east down the ridge crest where the best views are to be had.  The ridge trail ends at a junction with the Stewartville trail.  Turn left here to descend back down to the parking lot.

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