ApproachThis route is a traverse between Mts. Wynne + Pinchot. First you must summit either mountain. The most popular route on Mt. Wynne is the West Ridge Route, which is Class 2. There is also a Class 2 SE Slope, and East Ridge. The most popular route on Mt. Pinchot is the East Ridge Route, which is Class 3. There is also the Southwest Chute Route, which is Class 2, but only recommended as a descent.
Route DescriptionThe traverse is across broken, loose towers along the ridge that runs north from Mt. Wynne to Mt. Pinchot. I would only recommend this traverse in a northward direction (from Wynne to Pinchot). While it is relatively easy to prevent knocking off too much rock heading up the traverse, downclimbing it could prove quite hazardous.
Secor says "It is best to stay on top of the ridge, making minor variations onto the sides of the crest when necessary." Some other ascent parties have spoken of loose, chossy horror-shows as they attempted to stay off the crest altogether. Follow Secor's advice-- it's not as bad as it looks.
From Mt. Wynne, climb north down the ridge on easy, relatively solid talus. A saddle is hit. Quite soon you find yourself getting into Class 3 terrain, scrambling toward a large gap in the ridge, before the First Gendarme. Bypass the gap before the First Gendarme on the east side of the ridge. Climb the First Gendarme directly, staying on the ridge. Some rocks are loose, some aren't, just be cautious and you'll be fine. At some point, the ridge becomes very steep (possibly overhanging?). When you come to this obstacle, downclimb into a chute on the west side of the ridge, and climb the chute back up to the ridge above the difficulty.
You will soon find yourself on a wildly exposed catwalk. Continue making straightforward progress along the ridge. It will seem that some of the towers you climb are just going to fizzle out and leave you hanging in mid-air far above the ridge proper. But this never happens, and before you know it you are at the base of the easy Class 2 slope up Pinchot. Go straight up to the summit.
To be honest, it would be hard to see how this climb could stay Class 3. Secor rates it that, so I've kept it, but I'd say more like 3-4. I think you could probably keep it 3 on horribly loose rock, but if you allow yourself a few Class 4 sections, you can keep the climb on relatively solid ground.