Rattlesnake Peak P900 HPS
Lookout Mountain HPS

Thu, Dec 17, 2009
Rattlesnake Peak
Lookout Mountain
Story Photos / Slideshow Maps: 1 2 Profiles: 1 2


Rattlesnake Peak overlooks the San Gabriel River Basin in Southern California, an HPS peak of moderate proportions. There is no regular trail to the summit, but several use trails can be found to make things considerably easier than a jaunt through the chaparral would otherwise be. The trailhead is at the end of Shoemaker Canyon Rd, or rather at the end of the pavement where the road is gated. The road continues along the side of the canyon for several more miles through two impressive tunnels and then abruptly stops. Construction was begun in 1954 to provide an additional exit route for Angelinos in case of nuclear attack, but was abandoned in 1969 due to a combination of budget constraints, waning threat of nuclear attack, and mounting realization of the impracticality of the idea. Fifteen years and only 4.5 miles of progress were sober evidence of the latter. It was planned to eventually join the Angeles Crest Hwy at Vincent Gap, thus offering a way to the Mojave Desert through Wrightwood. One could only imagine what traffic along the twisty route would like during the panic that would likely precede a nuclear attack.

With nuclear war still held at bay and the road incomplete, I started up it on foot at 7:30a. With a starting elevation of 1,700ft, the road provides a fine overlook of the East Fork of the San Gabriel River, and the Heaton Flat area on the far side. In half an hour the first tunnel came into view as I hiked through the large V-cut in the mountain just before it. Engraved at the top with "1961", this first tunnel is perhaps 150yds long, mostly dry inside, and sporting a bit of tile artwork near the northern entrance on the right side. The second tunnel is perhaps 2/3 the distance of the first, and is encountered about ten minutes after leaving the first tunnel. It has the date "1964" engraved at the top.

Not long after leaving the second tunnel the roadbed ends somewhat abruptly and a use trail takes over, continuing to traverse the canyonside with only minor gain and loss in elevation. The brush had been groomed in a few places, yuccas trimmed (or otherwise made less deadly), and I had little trouble following the HPS directions for this route. Where the trail crosses over a rib of Rattlesnake's East Ridge, I started up the steep dirt gully that had been worn into the hillside. Once on the East Ridge itself, the route was obvious with the summit visible more than a mile away. The scenery was grand with the impressive Iron Mtn rising steeply across the San Gabriel River to the east. Far below I caught a glimpse of the "Bridge to Nowhere", the remnants from a 1930's effort to build a road up the bottom of the canyon (it was washed out in heavy rains and abandoned).

By 10:30a, three hours after starting out, I found my way to the summit. There were fine views of Iron and Baldy to the east, South Hawkins and Baden-Powell to the northwest, and a hazy view to the LA Basin to the south. I was amused by the benchmark labeled "FANG", wondering perhaps if "RATTLESNAKE" had been too much to stamp in the round metal marker. There was the standard red HPS cans, but no register inside, just a folded sheet of paper with names and entries from earlier in the year. Included was Rick Kent's entry from a bold attempt to climb Baden-Powell, Williamson, and Baldy in a day, via a route starting up Rattlesnake and then heading to South Hawkins. The route between Rattlesnake and South Hawkins had been his undoing, encountering extremely heavy brush enroute that sucked up too much time. Looking at it from the top of Rattlesnake, I was surprised that Rick had had the gumption to give it a go - it certainly looked awful.

I decided to take the South Ridge route back from the summit of Rattlesnake, just to mix things up and make a loop out of my visit. The South Ridge was in fine shape and obviously the most-used route to Rattlesnake. The route was well-groomed through short forest areas, along old firebreaks, and up the brushiest-looking section just past a small saddle. It took less than an hour and a half to get back down to the roadbed on the downhill side of the first tunnel which was just out of view around a bend in the road. As I was walking the last half mile back to the van I noted a dump truck driving up the road to unload a pile of debris at a wide clearing along the road. They were doing maintainence on the lower part of Shoemaker Canyon Rd overlooking the steep south-facing slopes of San Gabriel Canyon, and apparently using the closed sections of the road to dump the debris. Why they would continue to maintain Shoemaker Canyon Rd at all is a bit of mystery.

Once back at the van, I spent the next hour driving back down Shoemaker, then up Glendora Mtn Rd and east along Glendora Ridge Rd to Cow Canyon Saddle and the TH for Lookout Mtn. This HPS summit was the site of an important scientific experiment carried out in 1926 by physicist A.A. Michelson who mounted a set of lights and mirrors on the top along with a similar setup on Mt. Wilson 22 miles away which he used to make the first experimental measurement of the speed of light. As part of the experiment it was required that the distance be measured with extreme accuracy. The USGS carried out this part of the experiment and determined the distance to within a quarter of an inch. Or so they claimed.

The route from the south is only about two miles one way, but nearly 3,000ft of gain - a steep little bit of work. I walked past the locked gate heading north along the road for about 100yds to the entrance of the RV park that owns the approach road. The HPS suggests having a permission slip (printable from their website) along, but I had none. The place looked almost dead this time of year and I saw no one stirring about the few RVs that were lodged at the place. I began hiking up the south ridgeline to Pt. 5,696ft, looking for a use trail traversing left off the slope. Climbing too high, but unaware that I'd missed it, I moved left onto what looked like a weak use trail and followed this across the slope until I was fairly lost in a sea of chaparral. I struggled on and off for the next 15 minutes or so, thinking I was on to the trail, then finding myself bushwhacking again. Eventually I returned to the South Ridge I had started up and began to follow this upwards since it seemed my only route by which to make decent progress.

There seemed to have been a route up to the point at some time in the past, but it was becoming badly overgrown and I had to thrash a bit. It took almost an hour to go about a mile, pretty slow progress. The north side of Pt. 5,696ft was a good deal worse. The chaparral and trees grew to a height of some 12ft or more. Again, an old trail could be discerned in places, but mostly I was ducking and crawling through the underbrush as I made my way down to the saddle between the point and Lookout Mtn.

Once at the saddle a nice use trail coming in from the east was immediately evident. Though steep, the rest of the route up to Lookout Mtn was a breeze by comparison to the first half. The HPS guide suggests traversing right off the South Ridge and making a circuitious approach around to the north side, but this was wholely unnecessary. I simply followed the trail and accompanying ducks all the way up the South Ridge. A short rocky section was easily bypassed on the right side.

It was just before 3:30p when I reached the summit, with lingering patches of snow and fine views to the north of Mt. Baldy blanketed in the white stuff, similarly with the Three T's to the northeast and Cucamonga to the east. There was a register dating to 1998 and a reference benchmark at the top, the latter pointing to the main triangulation benchmark labeled "San Antonio" from 1922 about 40 yards to the south. This main benchmark was atop one of three concrete pillars, all that remain from the 1926 experiment. The register contained some additional details about the experiment that made for an interesting read while I breathed in the air from the historic summit.

I took the same South Ridge down to the saddle, whereupon I "discovered" the correct trail traversing around the west side of Pt. 5,696ft. By comparison, this route was wonderfully groomed despite heavy brush lining both sides on the northeast side of the point. When I got around to the firebreak I had started up earlier in the afternoon, I noted the non-obvious junction was much lower than I had expected. The "200ft" mentioned in the HPS guide must have referred to the total distance from the RV park, not the elevation above it that I had assumed. It was 4:20p by the time I had returned to Cow Canyon Saddle, where a most colorfully painted van was there alongside my own. I took a quick rinse in the parking lot just after the sun had set over Sunset Peak (appropriate, no?) before driving back down Mt. Baldy Rd to town. After a few hours of online catching up, I grabbed dinner and headed north on Interstate 15 to Hesperia where I slept off the side of the road east of town. I was to meet Tom in the early morning for some hiking and scrambling in the San Bernardinos over the next few days, a welcome change from the solo adventures of the past two days.


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