Ralston, who survived an accident in Utah's Canyonlands by amputating his forearm with a pocketknife—an experience that became the subject of the film 127 Hours—explains how he fell in love with the parks.

south rim
Credit: Getty Images

"The very first big life-changing experience of my adolescence was a trip to the Grand Canyon. At five in the morning, my dad woke us all up and loaded us into the minivan to watch the sunrise from the South Rim. It was so cold at 7,000 feet in the springtime, and there was a little bit of snow. I didn’t want to do it. But it was like watching the dawn of time as the sun came up over palisades of the desert, which run some 20 miles along the eastern border, illuminating the canyons below. I was 13 and from the Midwest, a complete Flatlander. My eyes got opened. We could see the river from where we stood. I fantasized about going down there and going rafting.

I’ve been to a lot of parks now. Denali was another great. I once pushed myself to solo climb and then ski from the summit of Denali. I said to myself, “Okay, this is either the boldest thing I’ll ever do or most foolish thing I’ll ever do.” If you don’t have the landscapes, you can’t have the experiences. These parks are my cathedrals. And I’ve gone back to the Grand Canyon to go rafting. I think I might be the only amputee to raft down the Colorado River."

As told to Lindsey Olander.

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