We didn't have much time, and just went a few miles out to see the Tafoni Sandstone Formation. The trail starts off of Skyline Boulevard in the mountains near Woodside. It's just three or four miles round trip with a little gain, and makes for a nice walk. The sandstone formation is quite impressive, and there's also a little viewpoint picnic area just a little further on where you can see out to the ocean on a clear day.
When we got back to the parking lot, we saw a sign directing us to the Methuselah Tree right across the highway and we decided to check it out. I'm not sure why our guidebook doesn't mention that it's worth it to take that extra .1 mile walk to see this enormous tree, because it really is! Most of the redwoods in this forest were cut down to build San Francisco, but a few old trees still exist. It's a treat to see them, but it always makes me a little sad wondering what this forest would have looked like if it hadn't been so intensely logged. This tree is estimated to be 1,800 years old and has a trunk diameter of 14 feet!