Grizzly Peak is the second-highest point in Oakland, at 1754 feet elevation (sources differ). As you approach it on Grizzly Peak Boulevard, it seems to loom quite high.
That’s an illusion caused by the eucalyptus forest. As you get closer, you start to see through the trees.
And from the bay side, the peak has a mohawk look because the trees are stripped off its northern half.
There’s a vague trail up the south side. Even in its true contours, Grizzly Peak is a steep little climb, and the thick layer of leaves is slippery. I’d rather the eucalyptus trees weren’t here, but they do offer a lovely privacy.
And underfoot are rocks! The peak is mapped as the Moraga Formation, a set of lava flows from 9 to 10 million years old. This is the stuff connected to the volcano at Round Top.
The top of the peak has a broadcasting tower of some sort, with a fenced-in support building at its foot. There used to be a lookout tower here, and a benchmark nearby attested to its elevation. Mount Diablo is almost exactly due east—not that you can see it through the damn eucalyptus.
You could walk up the access road instead. Either way, you can’t get any closer to the peak per se than this.
That route offers nice views, and it takes you past a lot of broken rock, if you have your heart set on a specimen.
Most of the rock is like this—weathered and fractured. There’s no easy way to tell what causes the strong layering, as this rock has been tilted almost vertical and then eroded by the fog, rain and earthquakes of the Berkeley Hills.
It’s hard to expose unaltered bits. What’s there is a medium-gray, featureless stone that geologists typically call andesite until they can study it in the lab.
Grizzly Peak is not a place to stay long, but it seems that there are those who love it.
Oakland Geology 
22 December 2014 at 6:37 am
Thanks – really enjoyed these pictures as well as your comments.