Alum Rock

Fri, Oct 14, 2011

With: Bruce Ramstad
Marty Sexton

Etymology Story Photos / Slideshow Map Profile

Alum Rock is a county park on the east side of San Jose, not far from my home. Penitencia Creek has cut Alum Rock Canyon on the western side of the Diablo Range, exposing interesting geologic formations as well as some hot springs. The hot springs used to be a big draw for local tourism 150 years ago, and a trolley track was run into the canyon to service this industry. The hot springs fell to disuse (they were more hype than anything else) and the place became a city park. There are two features named simply Alum Rock. One is the large monolith in the canyon for which the park and other features were named, the other is one of the highpoints above the south side of the canyon. It was this second objective that we were after on our semi-regular moonlight hike. Joining Bruce and I for the first time was Marty, an avid outdoorsman of the hunter/fisherman variety. He was easily talked into the outing based on its very modest stats - less than a mile each way to the summit.

With the help of Google maps I identified a good starting point with a small parking spot nearby, off Mt. Hamilton Rd to the south of the summit. We arrived around 10:30p, finding the location more then suitable, as it was a sufficient distance from any of the neighboring homes. Signs on the gate that we hopped just off the road indicated it was owned by the Santa Clara Open Space Authority, though it was not currently open to the public. An old paved road led up the other side of the gate to an empty platform that was probably intended to hold a home at one time, but never came to fruition. The pavement was in poor condition, heavily cracked with tall thistles and grass growing abundantly along its entire length. Though we all had long pants on, the thistles were sharp enough to poke through to our lower legs, and we had simply to accept this as a necessary annoyance. Stickers would collect in our socks as well for additional fun, but periodically bending down to pull out the nastiest of the bunch made things managable. The moon was several days past full and high enough to light our way without headlamps or flashlights. High clouds overhead covered perhaps half of the sky, but they were thin enough to keep from blotting out the moon when they passed underneath it.

From the end of the pad we hiked up an old road that was matted down some by a few vehicles over the summer, possibly by cows as well. We followed this up to a ridgeline that we could follow to Alum Rock. A small water tank was located here with an attached, open tub for watering the cattle that are grazed here. There were no cattle to be found tonight, but we did see three or four deer, does and fawns that were grazing near our summit. We crossed over two fencelines along the ridge. We had no road to follow in reaching the first of these fencelines, which took us out of county land onto private property. We noted headlights from two vehicles above us and very near where our summit was. We mistook these initially for house lights on a further-off ridge, but when they started to move we realized they were much closer than we had guessed. Luckily they moved and took off down a dirt road before we got anywhere close. Best as we could guess, the owners probably had driven up to enjoy the sunset and the inviting views of the city lights below. At a location on the adjacent property which we crossed first, there were several picnic tables set up at a small saddle with a delightful view to the city. It even had an old outhouse nearby, but we didn't check to see if it's still servicable.

Marty had brought several animal calls with him. One made a pretty good sound of a pig snorting, the other was intended to be a coyote call, but this latter one sounded more like a half-strangled bird call to me and I doubted it would successfully get a coyote to call back as Marty had hoped. It did manage to get a few dogs barking, but these were far enough away to not be a bother.

Above the saddle we found another steep road leading up to the next property where the two vehicles had been. Their tire tracks in the grass were evident. We avoided the road they had used in case they might come back, choosing instead to hike up an intermediate hill before dropping down to another saddle and then up to Alum Rock. In all we spent about 40 minutes hiking to the top. The summit is a rounded cover of lichen-encrusted rocks, not the towering boulder I had hoped for. The benchmark was found roughly in the middle of these, left by the Army Corp of Engineers in 1939. We took a few summit pictures, sat around taking in the views to San Jose, talking about hunting and property and the fine weather we were enjoying, taking about 10-15 minutes before starting down. Returning almost the same way (we used the road around the intermediate point since the vehicles were long gone), we got back to the car around 11:45p and back home shortly after midnight. A short outing, but a good one.

Anonymous comments on 10/18/11:
Hey Bob, are you ever going to release the write ups on the 2011 challenge?
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