Today's hike had me take a trip back through time as I visited Black Diamond Mines Regional Preserve outside Antioch. My destination would be a tunnel that sits as a reminder of a time when miners drilled into the rock walls of the preserve in search of coal.
I decided to brave the late July heat and make the prospect Tunnel Loop. The hike is a 7-mile loop to the park's western border where I would find 200 feet of mine shaft left open to explore. Originally drilled in 1860 as a 400-foot-long tunnel in search of commercial grade coal visitors can enter the first 200 feet of the mine shaft's rocky walls to get a glimpse of the mining operations that dominated the area from 1850 to 1900.
The hike to the mine shaft was a another summer special. I would work my way up the ridge line and head to the park boundary then turn down to the tunnel at the base of a set of hills. It seems like most of my hikes this summer have been ridge lines, mostly exposed with little shade and the prospect Tunnel Loop was no different. With the summer heat beating down on the park the hills have long since surrender any color and now a sea of golden hills sat before me as I made my way along the ridge.
The terrain is rugged, almost like nearby Morgan Territory. There are so many hiking areas that close by to each other that they share the same landscape features. Mount Diablo State Park, Morgan Territory, Round Valley, Los Vaqueros and Black Diamond Mines are all with a half an hour or so driving distance from each other. Along today's hike Mount Diablo's North Peak was a prominent feature in the distant landscape.
The sparse trees and grasslands didn't make for too much wildlife viewing except for the occasional ground squirrel darting across the trail. Vegetation was sparse but there were a few California Buckeyes beginning to hold their fruit. Mostly I made my way along the trail surrounded by the golden dry grasslands.
After a short descent for the ridge I reached prospect Tunnel. It is located off the main Stewartville Trail, reached by a narrow footpath leading from the marker at the main trail. Reaching the tunnel entrance it is a small opening hewn into the hillside. I could walk in with out stooping but the light quickly faded in the folds of rock leading into the tunnel. I didn't carry a flashlight today so I decided to venture in as far as I could and still navigate safely.
I made my way in for a dozen or so yards when I heard a strange flapping noise. My first though was I had disturbed a bat who was using the tunnel as his cave. The flapping was growing louder and in the dim light ahead of me I could make out something flying near the center of the tunnel. I switched on the built-in flash on my camera and guessing the focus as best as i could I fired the shutter when I thought i could see it getting close.
It turned out a bird was using the tunnel for it's afternoon roost and my entrance was not looked on favorably by the bird. With the flash exposure the bird would retreat further into the tunnel. I would take a few more steps in and the bird would approach me again. I'd take another picture and the whole process would start over. This went on for about 10 minutes as i tried to wait for the bird to get closer each time. My framing and focus was horrendous in the dim light but I managed to squeeze off a few frames where the bird was mostly in focus in the frame. After a while the heat in the tunnel was too much and I retreated to the comparative cooler temperatures of the trail.
My return trip on the trail was a another climb up the ridge from the tunnel at the base of the hillside. A pond, long dry the earth cracked and parched sat as an odd sight in the vast expanse of grass. A few more hills and I was at the starting gate and headed to the parking lot for a rest before the drive home.
The five towns that once supported the mining operations have long since disappeared slipping back into the dust that covers the trails. The tunnel is a reminder of the workers and life that once flourished in the park and is now all but forgotten. It was a good trip through time and an intersting tunnel leading us back to the past.