Casey and I went for a short hike to Aquarian Valley (the upper portion of Peter's Creek canyon), on 22 May 2004. These are some of the pictures I took.
We chose it after reading about it in one of Casey's climbing books. It wasn't a very long hike, but we came back at blazing speed, having forgotten an appointment Casey had. The hike starts at the Grizzly Flags/Long Ridge parking area, heads north along the ridge trail, and then follows an old road that turns into a trail along the creek. The old road starts just down Portola Ranch Road from where the ridge trail crosses it.
This is a valley that I somehow missed hiking in all of my years hiking up off of skyline, on and off trail. It's in the Long Ridge preserve, although there is a short section of the old road that is apparently an easement.
The variety of rocks (and their size) are quite impressive. We had our rock shoes, but it had been quite foggy, and almost all the rocks were covered with moss and lichen, so we didn't do any bouldering. The bouldering looks iffy, because of the moss, and the poor landing zones. Ignoring that, the valley and rocks are quite beautiful. The hike down to the top of the climbing area is fairly easy, but the canyon gets quite steep from there down. We had thought of heading back up a branching canyon to the ridge right near Ward Road, but as mentioned, we were short of time, so returned back up the canyon. Leaves something for another day! (It's also possible to follow the creek all the way down into Portola State Park; I've done the section further down several times.)