Devil's Hole at Las Trampas Regional Park

Not this weekend, but last, I went on a really interesting 6.5-mile loop (with 1,200 ft of elevation gain!) through Las Trampas Regional Park in San Ramon. This hike offered stunning views of the entire Bay Area, wind caves, and a "box canyon" called Devil's Hole. I was surprised to see that golden poppies and sky lupine were still blooming late into October. I am glad to have done it while the skies were still clear. We are experiencing a historic wind event that is spreading wildfire in Santa Rosa and bringing smoke down to the Bay Area.

I began at the staging area at the very end of Bollinger Canyon Road. From there, I took the paved version of the Rocky Ridge View Trail uphill as far as I could (they were doing some construction on the paved trail near its intersection with the parallel single-track dirt trail of the same name). There were lots of other people on the paved part of the trail, but once I got to the dirt trail, the number of people dwindled dramatically.

If you have a hiking permit from EBMUD, then you can take the Rocky Ridge Loop Trail, close to the top of the ridge.

The EBMUD trail goes along the Bay side of the ridge, whereas the EBRPD trail goes along the Mount Diablo side. Honestly, both seem nice. I liked my route and did not miss seeing the views of the bay, because I saw plenty of that later.

I took the Rocky Ridge View Trail until it intersected with the Sycamore Trail. This was both the hardest and the coolest part of the hike. The trail is quite narrow, not super well maintained the whole way through, and quite steep downhill at parts. First I went by a super interesting wind cave. There is a barbed wire fence to keep people off of this delicate geological formation, but you are so close that you don't need to scramble up--the cave is right there and it is easy to see it.

The steepest portions of the Sycamore Trail come after you cross the rocky ridge just south of the wind cave. This was the part of the trail that was hardest for me--it was tough on my knees, and I felt it later. I was a little worried that I would slip and fall. I went very slow to be safe, so this trail took me longer than I expected. You keep descending and descending, getting fresh and interesting views of the box canyon, where stone outcroppings make interesting patterns in the cliff faces that emerge on the steep hillsides. I can imagine that these produce beautiful waterfalls in the winter and spring months (although rain might make this steep path even more dangerous). It's mostly a chaparral ecosystem, and it feels very different than the grassy hillsides on the Mount Diablo side of the ridge.

At the very bottom of the canyon, you will see a few sycamore trees mixed in with the oak and bay laurel trees. They really stand out, with their beautiful bark and their light-catching leaves. Apparently, these trees give the trail its name. You will cross over the stream in order to finish the trail and join the Devil's Hole Trail. This trail goes steeply uphill, but the path is good. It's a wide fire road, but the dirt is tightly compacted and it does not slip. I wonder if it would feel safer to go down this way and up by way of the Sycamore Trail? I am not sure, because Devil's Hole is steeper even though it is a better maintained path.

In any case, the views of the Bay Area are stunning at the top of the Sycamore and Devil's Hole Trails along Rocky Ridge View Trail. You can see San Francisco Bay, Mount Diablo, the Sacramento River Delta, and the Livermore Valley. After making the hard (but satisfying) climb back up, take a moment to savor the view.

On the way back, I took the Cuesta Trail. This offered a slightly gentler descent back into the valley of Bollinger Canyon. I bet that this part of the trail is even more beautiful in the spring when the wildflowers are blooming and the hills are green.

This hike is definitely not one to do with young children. If you want to bring young kids to this park, then Bollinger Canyon Loop would be a better place to start.