I watched closely as my over-tied size 12 Adams tumbled off the gravel ridge and dropped atop the bucket at the head of a long run. The big dry swirled into the river’s current, forcing me to mend my line to extend the drift. A massive head the size of a grown man’s fist pushed from the water and sucked in the hapless fly. The floating fly line yanked tight, and the heft on the end of the line was admirable. I lifted the rod and knew I was into a big Rio Chimehuin brown. Like … really big. And then, just as quickly as the line had snapped tight, the fish was gone.

When Gregg Treinish set out to hike the length of the Andes Mountains at age 24, there was a lot he didn’t know. For starters, he didn’t realize he and his hiking partner, Deia Schlosberg, would be the first to do it. Or that their 22-month, 7,800-mile trek would gain them international recognition.

He also had no idea what he would do next — but he sure had a lot of time to think about it.