I am preserving the original Class 4 rating with respect of the first ascent team. However, you will be hard-pressed to keep the difficulty at 4th class on this route. Short 5th class sections are encountered throughout the route, and if you get off-route (not hard to do), you may be required to climb a couple of pitches of sustained mid-5th class in order to get back on the crest. Hence, this route is not recommended for a Class 4 climber. You should be comfortable soloing easy 5th and leading up to 5.7 if you want to increase your chances of success. Prior to us climbing the route, there were two known variations to the classic line. We believe that we established a third one, mostly due to our route finding errors. We missed the classic line and decided not to climb the unprotected "chimney variation". Our variation turned out to be more aesthetic and well protected than the "chimney" one. The classic route and all known variations are described here.
Classic Route (Class 4+): Stay on the right side of the buttress until you are about half way up. Follow the obvious gully/chimney system that leads to the left. At the end of the chimney, go right and up until you gain the crest of the buttress between the two prominent towers. Climb around the higher (2nd) tower on the left side until you find the steep gully/crack system that leads back to the crest right below the summit block. The summit block can be climbed directly from the crest, or from the right side (easier).
Variation (Class 5+): After reaching the top of the gully/chimney system half way up the buttress, go over the crest of the buttress on the left and drop down the Southeast Face a little bit until you reach the obvious sandy gully. Follow that gully up until you reach the squeeze chimney. Climb up that chimney for 70-100' as it leads you to the crest of the buttress between the two towers. The chimney is relatively low angle in the beginning and steepens up towards the end. It is poorly protected and will require a lot of free soloing. Not recommended with a pack.
Variation (5.7): From the bottom of the chimney described in the previous paragraph, climb the crack system directly to the top of the lower (1st) tower for approximately 200'. This crack system is located on the right side of the chimney. The rock here is mostly vertical and well-protected. Approximately 2/3 of the way up, there will be a vertical squeeze chimney filled with loose blocks. Unless you are petite and can fit into that chimney, it is better to climb around it on the right side (arete with lots of chicken heads). An intermediate belay station can be set up on the sloping ledge above the chimney. Once you top out on the 1st tower, you can unrope and follow the crest until it merges with the classic route.
Direct Route (III, 5.9): Follow the crest of the buttress the entire time. Spectacular, very exposed and much harder climbing will be encountered throughout the route.
Immediately after Trail Camp (12,000'), leave the Whitney Trail and hike over talus towards the toe of the East Buttress of Mt. Muir. Depending on the season, several snowfields may need to be crossed or walked around. Total elevation gain between Trail Camp and the beginning of the route is 650 feet.
Follow the regular 3rd class route down to the Whitney Trail. Take the Whitney Trail back to Trail Crest.
Light alpine rack: a set of stoppers, one set of cams up between 0.5" and 3", lots of slings to minimize the rope drag. Ice axe may be useful early in the season.
BETA PHOTO: Etsuko is negotiating sandy ledges and gullies low...
BETA PHOTO: Looking up the new variation of the East Buttress ...
BETA PHOTO: Etsuko is in the sandy gully on the South East fac...
BETA PHOTO: Looking at the new variation from the crest of the...
BETA PHOTO: Typical broken terrain on the East Buttress of Mt....
BETA PHOTO: The summit block of Mt. Muir from the top of the 2...
BETA PHOTO: Etsuko is soloing the easy 5th pitch next to the 2...
BETA PHOTO: Etsuko is soloing easy 5th on the lower part of th...
BETA PHOTO: A view of the existing (green) and new (blue) vari...
From: Dali, Yunnan Province, China
Sep 10, 2013
Update as of 9.8.2013
Not sure how this may affect conditions on the East Buttress route, but a huge rockslide swept down the East Buttress/face of Mt. Muir on Sunday, late morning on Sept. 8. Haven't heard our found much in the way of news, but there is a big rock scar visible 1/2 to 2/3 of the way up the face.