The West Face is both the easiest and fastest route up Mt. WIlliamson, but don't let that fool you. This is still an arduous undertaking involving 10,500ft of elevation gain and 27mi roundtrip.
The trail starts at the Shepherd Pass Trailhead. From the hiker's parking lot at 6300ft, it follows Symmes Creek for a little more than a mile, crossing the creek four times. 53 switchbacks then take you up over 2,000ft to Symmes Creek Saddle where you'll get the first views of Mt. Williamson and its impressive North Face.
At this point the trail heads downward for over a mile, crossing two lower saddles and dropping a total of 500 feet (ugh! on the way back) towards (but not reaching) Shepherd Creek. While this may seem insanity in trailbuilding, the loss in elevation is required to surmount two obstacles: the lower portion of Shepherd Creek has steep cliffs making a trail up from the bottom impractical, and secondly, the loss coming down from Symmes Creek Saddle is needed to get around obvious cliffs that line the north side of the canyon.
The low point coming down from Symmes Creek Saddle is where the trail just skirts under the cliff rocks. It then traverses up towards Anvil Camp. Not far from the low point, the trail crosses a stream with the only water available until Anvil Camp. Stock up if low, or planning to camp at Mahogany Flat or another site before Anvil Camp. The trail climbs up again, via very long switchbacks to Anvil Camp at 10,300ft. The trees start just below Anvil Camp, and end about a mile above - if you value shade for camping, consider camping here.
The trail crosses the creek one last time at The Pothole, about a mile above Anvil Camp. From here it is two more miles to Shepherd Pass at 12,000ft, mostly through moraines (you'll thank God there is a trail through this tough pile of rubble), and The Pothole is the last reliable spot to get water until the pass. The last 500 feet climb steeply, often over snow unless late in the season or low snow years. The snow is easy to cross when soft (and pre-stepped), so plan your crossing here after the snow has been in the sun several hours. Crampons and axe should be carried in early season or if unsure of conditions.
Wow - you've now climbed 6,200ft and 11mi, and you're still several hours from the start of the route. If you haven't dropped your pack at Anvil Camp, you're likely to want to do so now at Shepherd Pass. The nearby lake provides water year-round and makes this a popular camp site. From here to the start of the route there are three additional lakes that provide water year-round and also make swell campsites - it all depends on how hard you want to work on the approach and how easy to make the summit day. If you don't make camp at the pass, be warned that travel is now cross-country and gets considerably harder once you enter Williamson Bowl.
From the pass, head east up towards the Sierra Crest over gentle, sandy slopes. Mt. Tyndall looms to the south - if it looks hard, be warned that Williamson is quite a bit harder. As you climb the sandy slopes, Mt. Williamson's West Face will soon come into view, an impressive sight indeed (the tip of the peak is also visible at the pass, but disappears again until you reach the crest). Keep to the right (north) side of the crest where you'll find the low point in the crest. A sign warns you that you are about to enter the Bighorn Restricted Area which is closed July 16 through Dec 14. Please respect this sign and the restricted area (which includes all of Mt. Williamson), and don't climb Mt. Williamson after July 15.
At the crest, you'll have a grand view of Mt. Williamson and the infamous Williamson Bowl. You can spend a great deal of time trying to pick out Secor's description and recognize the picture found in his book - save yourself the trouble. The start of the route is on the far right of the West Face, at the end of Williamson Bowl. The picture in the book was taken from the highest (and farthest) of the lakes found in the bowl, and simply cannot be deciphered from the crest. Williamson Bowl is composed of four lakes and piles and piles of boulders and scree. No matter how you cross it, you'll find the nearly two mile journey tedious. From the crest, drop down about 300 feet, heading for the highest ridge that runs down the middle, roughly NW-SE between the four lakes. This route seems to be the most used through the bowl, and consequently the talus and sand are more compact here than elsewhere, and there are even faint vestiges of what looks like a use trail beginning. About halfway across you'll need to veer right to avoid a cliff, climb down and around towards the highest of the Williamson Bowl Lakes. The north side of this lake marks the best vantage point from where to view the famous Black Stain and the start of the West Face route.
The West Face was used for the first ascent of Mt. Williamson by Joseph LeConte, Edward Parsons, and five others in 1903.
From the north side of the highest lake, climb towards the prominent black stain on the right side of the West Face. You cannot see the class 2 chute above the stain until you climb up to it, and have to take it on faith that it is there. Secor says it is the largest black stain, but I'm not sure I agree. There is a larger section of black rock further to the right, but that leads to the Bolton Brown route. The large stain Secor refers to is black due to water - in fact it is the snow melting in the class 2 chute above that bleeds down and runs over the rock here. Climb to the Black Stain over tedious talus and boulders. The stain can be bypassed most easily on the right, but be warned that the slopes are steep, loose, and sandy. The stain can be climbed directly via numerous class 3 lines over mostly solid rock - it is more enjoyable to climb through the stain than around it.
Above the stain you'll be looking up into the class 2 chute that runs diagonally up and to the left (north) across the West Face. In early season this chute will have considerable snow in it, and is probably preferable to the loose crap that lies underneath. If you find yourself in the chute in July, it will be mostly snow-free, but slow, loose, fairly crappy climbing all the way to the top of the chute. As you look up you can see a massive wall blocking the chute at the top - this indeeds marks the top of the 1,500-foot chute where it meets the Northwest Buttress. You might find more solid climbing on the left and right sides of the chute, but it rarely lasts long and the zig-zagging may be more frustrating than the direct line.
Before you reach the massive wall at the top, veer right towards the class 3 chimney which should be fairly obvious from about 200 feet below the top of the chute. If you want to to climb the chute to the ridge, you'll be rewarded with a wonderful view of the Owens Valley and the Shepherd Creek Canyon you climbed earlier. You can reach the start of the chimney from the top of the chute (if you went for the view) more or less directly by traversing right about 100 feet from the top of the chute.
Congratulate yourself. The tedious stuff is now done as you stare up an impressive 100-foot chimney. This class 3 section may look and feel more like class 4 at times, but you should be able to find excellent holds for the entire route without ever having to subject yourself to more than about 10 feet of exposure. The climbing here is highly enjoyable in fact, and wonderfully refreshing after the hell that makes up that chute below.
The top of the chimney brings you out to the summit plateau. The West Horn is distinctly visible across the plateau to the east. The summit is to the right, less than 500 feet up. The more enjoyable climbing is found on the ridge; looser, sandier climbing if you first descend to the plateau and climb around from the north.
Ice axe and crampons in early season (before July), otherwise nothing special aside from a good pair of boots that can take the boulder-climbing through Williamson Bowl.
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