Give it a minute to download. This was a day hike me and josh mckague did in the rocky mountain national park.
From 9405 ft to 14255 ft above sea level, the highest point. Something harder happened since that hike, but up until then it was the hardest thing I'd ever done. Josh didn't make it all the way up because of the pain in his head, see it's so high up that everything decompresses and that hurts, and you can't breathe because the air is so thin, and that makes something like a tough hike excrutiating.
I made it to the top, but I did not make it back. I'm still there at the peak, on those boulders, with that wind, and that sun, trying so hard to catch my breath.