Oh dang, I am reminded fondly of the one Acadia peak I climbed that had something similar --iirc, essentially giant steel staples rammed into the cliff face to help you get up the otherwise sheer bits!

(I am less good at tracking peak names, and Acadia-trip was during the not-writing-every-day times, so I can't at all remember what exactly it was)

This is cool though! I feel like I should be making a little notes file from your posts for my own eventual "in beauty I walk" trip to California!