From Willoughby Mountain it's 90% Class 2 hiking along the connecting ridge. There are obvious use trails underneath some of the ridge bumps. The last bit to 13,020 B's summit is Class 2 and it's obvious where the change happens - a sudden shift from grass to broken, stacked shards and boulders of the Capitol/Snowmass-type rock. The ridge is easy at Class 2+, maybe a tiny bit of Class 3, but the rock is of course loose. Exposure is moderate, I found it easiest to just stick to the ridge crest which was kind of a jagged knife edge of broken blocks but not really hard in any way.
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