Frank and John Shafer needed a way to get cattle from the mesa tops, onto the shelf of open sage and brush—and the Colorado River—some 2,000 vertical feet below them. So they did what any ambitious cattle rancher in 1914 would have done: They built a trail. In the 1950s bulldozers widened the trail to facilitate the uranium boom. I can only imagine how many cattle fell to an untimely death in those early days of herding them off the top. Shafer Road is one of the most impressive engineering accomplishments in the United States. At least, it is from an improbability perspective. And while several jeeps and trucks creak and moan their way up and down the road each summer, I think it is most appreciated on a bike.