When Forrest Fenn was given a fatal cancer diagnosis, he hid a treasure chest in the wilderness in 2010, and published a poem that would serve as a map leading to its location. But he didn't die, and so Fenn instead presided over a decade-long gold rush that saw many thousands of treasure hunters scrambling across the Rockies in pursuit, with some of them dying in the attempt. Daniel Barbarisi took part in the search, and here he shares his story and recounts how one hunter would ultimately find the chest—but the mystery didn't end there.