Distance: 8.3 miles round trip on dirt road and use trail
Summit Elevation: 4360'
Elevation Gain: 3435'
Elevation Gain (in Empire State Buildings): 2.74
Round trip time: 5 hours 15 minutes
Recommended water: 154 oz.*
Parking/Fees: Free on Ridgeside Drive
* I took 128 oz and ran out, recommend 154 oz in the summer
Another Sierra Club Great Lower Peak in the ANF between Mt. Zion and Mt. Bliss. I did the alternate route starting on Clamshell Truck Trail, then up the firebreak. I very much underestimated the effort and water required for this hike. I parked a little ways away from the driveway that leads to Clamshell Truck Trail. The road starts out with a gentle gain and winds around Ruby Canyon about a mile until you reach an obvious firebreak going up on the right. There was a Monrovia ranger truck parked there with the windows down, but no ranger in sight. I started up the firebreak wondering if I would run into him doing some kind of maintenance or rescue, but I never saw anyone and the truck was gone when I got back. The firebreak separates Ruby Canyon from Clamshell Canyon, and is easy to climb at first. A very steep section starts at the 2 mile mark and gains 1500' in the next mile. Worse, it is over loose dirt. A few times, I grabbed small brush or large clumps of grass to aid my ascent.
After topping the initial ridge, the trail deteriorates into criss-crossing animal trails. I also found a pink metal marker after the first steep section but no benchmark or sign. Going up, it was pretty easy to stay oriented, but not so coming down. The last mile to the summit only gains about 950', but sections of animal trail are completely overgrown and must be bashed through. The vegetation is mostly knee high to waist high grass, weeds, and other soft plants. At the very end, the trail opens back up onto the overgrown Upper Clamshell Road, a welcome change. No poison oak on the ridge line, but there is a little poodle dog bush. There is almost no shade the entire way except a few smallish trees that provided a few square yards of relief. You climb over numerous bumps and a false summit, never seeing Clamshell Peak until near the very end. The summit itself is flat with good views of Rankin/Monrovia Peaks, Bliss, and Mt. Wilson. I found the summit register in a buried concrete bunker under a large iron grate. Spiders had built webs over the register cans. I cleaned up the cans and unwrapped the registers from 6 plastic bags. There were two small notebooks, one going back to 1987. Before me, Clamshell was last visited in April. It is not visited very often. I signed the register and returned it to the concrete bunker. I forced myself to eat something, but the heat had killed my appetite.
Soon, I started down, following the same animal and bushwhacked trails. I blindly followed the best animal trail right down the wrong ridge. When the area started looking unfamiliar, I checked the GPS and saw my mistake. I had to climb 100' back up to find the path down the right ridge and that is when I ran out of water. I took 128 oz, but needed about 154 oz, and put that number in my summary. Back on track, I could not descend too quickly due to the angles and loose dirt. While difficult, it was still much easier than going up. Without water, I was dehydrated by the time I reached the road, and even more so when I got back to the car. Fortunately, I had plenty of water in the car and did nothing but drink until my thirst abated. My stats reflect my mistakes. With no errors, the round trip is 8 miles and 3335' of gain, with most of the gain concentrated in the last two miles. Light bushwhacking both ways and some route finding needed on the way down. I can see why some people continue over Rankin and Monrovia because most of the gain is done by the time you get to Clamshell and you don't have to come down the steep dirt. Clamshell is a tough little peak on this route. It was my 100th listed Sierra Club peak.