Went up and down Washington as a group of 20 somethings. Boy were we suffering on the way down. At one point below the treeline as we are crawling down, these two guys catch up to us; they looked like they were in their 60s. Grey hair, thin as twigs. They whooshed past us literally hopping rock-to-rock. That one little moment had a lifelong impact on me ever after as I though how nice it would be to be able to do the same at that kind of age.