Tunnel vision

Hiking partner Alice and I wanted to take a hike this weekend and thumbing through my California Hiking book I came a cross the Prospect Tunnel Loop hike. Located in Black Diamond Mines in Antioch it sounded like a nice 5 mile hike with a chance to explore 200 feet of an abandoned and closed off coal mine along the way. Sounded fun and we headed out Sunday morning for our hike.


Black Diamond Mines is the site of coal mines that operated from 1850s to the early 1900s. Several small towns sprang up around mines for the miners and the families. Little remains except a cemetery and visitors center while the vast majority of the sprawling mine complex has been returned to open land for hiking and bicycle riders. Alice and I hiked a portion of the park last November when the weather was cooler but were determined to make the full loop on our Sunday hike. The loop spans most of the park lengthwise with a short detour to the Prospect Mine tunnel.


Our route would take us along the Stewartville Trail to the Ridge Trail and then on to the Corcoran Mine Trail with a return route looping back to the Ridge Trail. It looked easy on paper but as we would find out it would be a grueling hike coming close to Mount Diablo’s Eagle Peak hike in strenuous effort and heat.


As a late July hike Black Diamond Mines can be brutal. The landscape is a mix of open grassland and chaparral. The trails are mostly wide dirt paths cleared from the grassland. The trails wind up and down the ridgelines although at times they seem like they mostly head straight up. The cautious hiker brings plenty of water, sunscreen and a hat to combat the summer sun.





We headed out on the trail and as most of our hikes have been this summer I am struck by the dry conditions. Yellow grass rolls up and down the hillsides all around us as a testament to the dry conditions we have this year. Thistles along the side of the trail are were wilting in the heat some still bearing a trace of the purple flowering others black from the sun. Live oak and California buckeyes scattered along the floor of the canyons as we headed higher and further into the park.



Heading higher we paused often to catch our breath at the few shady spots along the trail. The canyon walls funneled the heat toward the trail and it seemed we walking through an oven as we pushed on to the mine tunnel. Just about 3 miles along the trail we reached the Prospect Tunnel junction, a narrow winding path leading the shaft entrance up along hillside. Flashlights ready we stooped down to make our way along the 200 feet of the mine tunnel still open to the public.


Light glowed of the ridges along the walls as we explored deeper into the tunnel. Words have been carved into the walls and ceiling, some looked like names others were hard to read in the dim light. Ore veins lined the tunnel as a reminder of the tunnels early use. The deeper we explored the hotter it got and we quickly got our shots and headed back to the trail for the long walk back to the car.


The afternoon breeze helped as we climbed back to the ridgeline. With about a mile of trail left to hike Alice and I were both out of water as made the final stretch of climbing. The steep grades on the trail and heat reminded us both of our hike on mount Diablo’s eagle peak. I was starting to think that the Prospect Tunnel loop was reaching Eagle Peak territory as my claves and ankles ached and burned with each step.




Finally we reached the downhill path to the trailhead and our walking was easier with a stiff breeze that pushed us along. Sipping Gatorade at the car I checked my GPS unit to find our hike had carried us 7.25 miles through the park in stifling heat. It was a good hike, a little on the hot side but the great exercise and great views of the park. We are thinking about making a return trip to the trail in March for greener scenery and cooler temperatures.