Gastro BM P750
Mine Mountain P300 CC
Mustang Peak P300 CC
Penasco Rock CC

Thu, Apr 5, 2012
Story Photos / Slideshow Map GPXs: 1 2 Profiles: 1 2

With the approach of the full moon, none of my regular night-hiking partners were available to join me for a Thursday evening outing. As a result I looked to do either a harder hike or longer drive than I would otherwise do, settling on a visit to the southern part of the Diablo Range between Fresno and Monterey Cos. In order to make the long three hour drive more enjoyable, I left San Jose at 5p so that I could enjoy the scenic drive in the late afternoon and start the hike just after sunset. Spring rains had brought green hillsides to most of the range, and the drive down SR25 through Hollister and past Pinnacles NM was most enjoyable in the convertible. The moon rose shortly after 7p. From SR25's southern end I drove east on SR198 for 24 miles to the narrow but paved Parkfield Grade road and took this for some 8-9 miles to the crest of the range where the pavement ends. My goals tonight included three CC-listed summits and the highpoint of the area with 730ft of prominence, Gastro BM. This last was first on the agenda, located little less than a mile to the west from the top of the grade. Just after 8p I found a suitable place to park off the pavement near a gate to a dirt road that leads to the top.

The hike up to the summit, only 400ft of elevation above the start, took all of 14 minutes. A microwave relay tower with a bevy of solar panels are found at the top that has been bulldozed and graded with dark-colored gravel. The bulldozing appears to have wiped out the benchmark which gives the summit its name, though I did manage to find a reference mark from 1961 pointing to the missing benchmark. The few views to be had from the top were mostly unremarkable, though it was clearly the highest point around for about 8 miles. By jogging, the return was managed in less than 8 minutes.

I next drove over the summit and down the dirt road that heads into Parkfield. The road was in decent shape, but wet weather can make it impassable. I had only driven two miles of the dirt road before coming to the start for the other three summits. Near as I can tell, all the lands I traveled for these three peaks were either used for ranching or hunting, possibly both. Mine Mtn and Mustang Peak both lie on the crest of the Diablo Range between the two aforementioned counties. A dirt road runs up from where I started to the crest, then along the north side of the crest, passing by both summits. This land appears to be owned by a hunting club as the various forks are clearly labeled with names such as "Fresno Trail" and "Hardway Trail" to help the unfamiliar with navigation (assuming you have a map to the area with the trail names shown).

I spent about 45 minutes hiking to the summit of Mine Mtn, the last 50 yards or so on an overgrown firebreak along the crest. One could view the lights of the Central Valley to the north and northeast, with softer, moonlit views of the interior of the range in other directions. It would take another 40 minutes to reach the summit of Mustang Peak which proved trickier. There is a very large hunting cabin found on the north side of the peak that is under construction and looks to have been so for quite a few years - possibly one of those dreams where the size of the available funds don't quite match the size of one's vision. I followed the road past the large clearing where the cabin was, looking for an opening in the brush to allow me to reach the summit. To my surprise it was a solid wall of brush and trees over 12ft high all the way to the saddle where the road begins to drop down. I retraced the quarter mile of road back to the cabin where I found a clearing up to the summit in the understory on the northwest side. Just below the summit is located a lookout tower with a 20-foot ladder leading to a perch to allow a keen observer to watch for wildlife. 50 yards beyond this through some brush was the actual summit, though views were impossible to obtain, surrounded by thickets on all sides. I made the mistake of trying to follow the East Ridge down to the saddle I had reached earlier by road. It looked like I might have success, as the ridge had animal trails along it for much of the way, but not 30 yards from the saddle I was stopped when the brush grew thick and I noticed poison oak all around in front of me. It was a bit of a pain to climb back up to the summit again, but better than suffering from the poison oak the next day as I surely would have done.

The last summit on the agenda was Penasco Rock, an outcropping of volcanic rock several miles north of the crest and more than 1,300ft lower. It was not clear at all how such an obscurity was chosen for the list, but the effort to reach it proved to be as interesting in practice and it had appeared from all the map work I did beforehand. There are no roads that I could discern connecting the two, but several branches of roads from above and below looked to get fairly close together, requiring maybe half a mile of cross-country. In addition there were several property boundaries to cross and as is sometimes the case, the roads near or between the boundaries are the most unused and often in the process of decay. I was fortunate in two aspects. First, the road leading down from above was decent enough to get me through the thick brush found along much of the crest. Secondly, lower down where the cross-country took place was land grazed by cattle. These slopes were far easier to negotiate, though it was still a tricky (and enjoyable) affair to find a route down through the oak forest on steep, grassy slopes.

Where I picked up the expected roads from the ranchlands below, I also encountered a large herd of cattle that were not amused by my sudden appearance in their sleepy landscape. They took off running until out of sight, unfortunately in the same downhill direction I was heading which meant the scene of being discovered and setting them off running again would occur half a dozen times. It wasn't until they had gone something like a mile and were situated below Penasco Rock that they were left in peace. In all I spent about an hour and a half going from Mustang Peak to Penasco Rock. The outcropping turned out to be much larger than I'd expected and was really the most interesting summit of the entire evening. The south side from which I approached looked steep and difficult in the moonlight, but proved no more than class 2. Upon reaching the top of the sharp ridge perhaps 30 yards long, I peered eerily over the north side that dropped away in a cliff of more than 100ft. It provided for a dramatic view off that side across the Jacalitos Hills to the lights of Coalinga just beyond. To the south rose the higher crest of the range, with the highest point for many miles being the 4,300-foot Black Mountain to the southeast (with 1,800ft of prominence, and oddly not on the CC list).

I cut about a mile off the return route by not retracing my steps back to Mustang Peak to the south. I had picked out another cross-country route that bypasses both Mustang and Mine, the satellite views having helped greatly in finding the best way across Jasper Creek and then up the steep slopes to the road on the crest. I had worried about the presence of ticks in these hills (the area had been infested with the critters when I visited in the fall about 20 miles from here), but was happy to find only two of them on my pants all night, despite several miles of cross-country travel. It was 1:20a before I returned to the car following a very enjoyable outing. It would be 4:30a before I would get to bed that morning, but well worth the loss of sleep...

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