In reply to Ratfeeder:
Yes, I initially skipped the beginning to get to the climbing scenes but then watched it through a second time as I liked the characters and wanted to know the background story.
The climbing language felt credible debating the routes on the north face v south face, getting a first winter ascent, noting the chimney would be iced up in winter, but the alternative is to be wet in summer! It all felt very honest compared to modern attempts the the infamous bolt gun in cliff hanger.
There is criticism of casting the leads as brothers rather than father and son but that didn't bother me.
It's on Netflix if you know anyone with an account