Castle Rock is actually “Castle Rocks,” to be more accurate. It is the series of post-volcanic rock masses that have formed adjacent to Mount Diablo State Park. From the marked trails, you can see the huge formations towering overhead, but for a better treat, head off trail and go explore the rocks and caves up close.
Our group was headed to the Juniper campground, an overlook spot about two-thirds of the way up Mount Diablo, but, as it often is, the best part of the hike was not the destination but the journey. We started at the Castle Rock Recreation Area, which is in Walnut Creek and part of the Diablo Foothills Regional Park. The area has equestrian stables, a community pool, lots of picnic areas, and several other recreation options. I can’t recall the last time I started a hike and saw a basketball court by the trailhead.
In any case, there are a few routes to head into the park, and at any point, you can cut over to the southeast and head to Mount Diablo. We stayed in and around the large rocks for awhile, and then did some serious off-trail exploring as we headed into the state park. It was a picture-perfect California weekend – 70s and sunny nearly everywhere in the Bay Area, but while that usually means lots of traffic on the trails, because we were meandering on single-track deer trails and heading across the brush itself, we didn’t see many people, making it a fairly secluded hike. That can be a luxury around here on spring weekends.
Hiking on a warm day also means being more prepared, with extra water, sunscreen and food. Our group had an impromptu beer/wine/cheese cocktail party midway through our hike thanks to a new member of our group who treated us all to a mid-hike spread, so that meant we hiked the last couple of hours in the dark, using our headlamps and flashlights to find our way out. Our zig-zag route across Castle Rock and up and into Mount Diablo included a total climb of nearly 4,000 feet, and a hiking distance of 14.4 miles. Not a bad workout at all.
As we climbed, there were terrific views of red-tailed hawks and, I think, falcons swooping through the valley. Also, Mount St. Helena and the Sierras were visible in different directions. This hike wrapped up a handful of Mount Diablo-area treks in a row for me, part of a chance to dive deep into one area, wander around the trails and see it from all vantage points. It has also been an opportunity to learn a bit about the Volvon and Miwok tribes that settled in this area, and to see some of the physical evidence that the earliest folks left behind. In a few cases, the well-chiseled rock faces are now marred by graffiti (see picture below), but generally, the remnants of those Native American villages are still there to be viewed, respected and shared by modern-day explorers like us.