In the early 2000s, I (Rickey) lived in Boulder, Colorado—first as a student, then as a waiter and bartender, and finally as a barely sponsored distance runner living off the grid for cheap. As goes with the territory, when a friend needed someone they could count on for a belay, I also climbed. I climbed enough to love it, but not enough to live it. I left the world of climbing with three things: tendinitis in my calloused hands, a small collection of carabiners and belay devices that I’d never use for their intended purpose again, and the holy grail of North American climbing—Steve Roper and Allen Steck’s book Fifty Classic Climbs of North America.

The book enthralled me, perhaps even more than climbing itself. Though I had completed a couple of the classics in the book—thanks in large part to the patience and skill of others—its greatest power was that it made me dream about what that list would look like in the burgeoning world of trail running. I was certain that the Grand Canyon’s Rim to Rim to Rim would be on the list, as well as the Presidential Traverse across the White Mountains of New Hampshire, but what were the other 48?

Ideas are cheap and don’t survive in a vacuum. Though holding on to this idea for over a decade cost me nothing, it was clear that it was going to take me the rest of my life to complete. Luckily, in early 2024, I learned through a mutual friend that two others, Andy Cochrane and Ian MacLellan, were working on a nearly identical project inspired by the same book.

A brief phone call allowed us to compare notes and working styles. I admitted that, given the inherently subjective nature of a curated list of trails, I was hesitant to work with others. Andy’s approach was the polar opposite of mine. He originally envisioned the project as entirely crowdsourced (which is how Ian learned of it). The simple fact that the three of us were actually having a civilized conversation about this project was all the proof I needed that collaboration was the only path forward. Furthermore, that our lists of trails largely reflected one another’s confirmed that Ian and Andy were the right collaborators.