The world’s longest mountain bike route zigzags 2,490 miles along the Continental Divide from the Canadian border near Eureka, Montana, to the Mexican border at Antelope Wells, New Mexico. In the process, it climbs 200,000 feet (that’s seven Everests) and ascends passes two miles high. Naturally, the first nation-spanning fat tire route encompasses the best of our Rocky Mountain spine: alpine wilderness, undulant grasslands, scrub desert, solitude that frays the edges of your brain, and a sense of what the country would look like if wilderness were the rule, not the exception. Yet the signature of the Great Divide Route is its doability. It was purposefully scouted and mapped over a decade ago by Adventure Cycling to intersect civilization virtually every day. That eliminates the need to schlep a heavy larder or to arrange complicated food drops. Most of the ride is on doubletrack forest roads, with rare technical bits and a smattering of asphalt. While zealots race it unsupported in just over two weeks, anyone with true grit, good gear, and a Suze Orman–approved budget can do it in just over two months. Or riders can select a single state and call it a dream vacation: Montana is 20 days and 695 miles (the majority surprisingly easy) from the wild alpine country near Glacier National Park to the big grassy basins in the south.

Need to Know: For maps and trip planning advice, visit the Adventure Cycling Association online (adventurecycling.org).