For this hike, I was on my way back to the Bay Area from Truckee after Labor Day weekend, and I wanted to hike no more than about 3 hours without too much extra driving. This segment of the Bay Area Ridge Trail fit nicely with my constraints, and the Big Rock starting location sounded interesting. One of the things I’m enjoying about hiking the Bay Area Ridge Trail system is that most of the trails are first-time hikes for me, which always adds an extra element of intrigue.
Lucas Valley Road, the road to Lucas Valley Open Space Preserve, departs from US-101 about 4 miles north of San Rafael. The trailhead is approximately 6 miles from US-101: basically, you drive along a nicely twisty road until you reach the summit, where the trailhead is marked by the aptly named Big Rock.
It was a warm day, and most of this trail is very exposed and sunny. Initially the breeze felt cooling, and later was warming coming across the warm hills. There were a few spots of welcome shade. Most of the trail is within the OSP, but there is a section that leaves the preserve and continues through the adjacent private property owned by the Lucasfilm Company, using an easement granted to the Open Space District.
As described in the official BART guide, the trail is nicely graded with an average grade of about 7%. I would describe the hike as fairly straightforward. There were pretty views of the surrounding Marin County hills, beautiful examples of California golden hills in their summer hues.
Near the top of the Big Rock Ridge, the trail follows a fire road for a ways. I did manage to miss one place where the trail leaves the road – I stayed on the road instead of the intended trail, and as a result I hiked to an incorrect summit before going to the correct one. (The detour is easy to see on the GPS track.) In retrospect I should have realized that the highest summit – the real one, if you like – is generally the one with communication towers. From the top there was a great view of the Tiburon Peninsula and San Francisco in the distance to the south.
I seem to always enjoy climbing to the top, whether it’s a hill, a mountain, or something man-made such as a tower, for the view. After enjoying the view here, I headed back to my car. The temperature had risen about 10 degrees during my hike, to about 90F, so I was glad to be able to run the air conditioning to cool off. The hike would have been even more pleasant in cooler temperatures; I just happened to select a relatively warm day.