If the Maah Daah Hey were in Utah or Colorado, it might rank as the country's most popular trail. Instead, this 120-mile-long swath of singletrack rambles across the remote badlands of North Dakota, far from the mountain bike masses.

The ride swoops across flat-topped buttes, vast grasslands, and wide-open cattle ranges. Along the way, mountain bikers descend multicolored striated hills and pass through sandstone hoodoos that—like enormous chess pawns—seem to stand guard over broad valleys. Rarely will you see another rider.

Much of the trail is formed from betonite clay, which makes for a fast and smooth surface. But this is no cakewalk: Riding the Maah Daah Hey involves more than 13,000 feet of climbing and descending. "You're in a constant state of up or down," says Nancy Morlock of Escape Adventures, which runs multiday trips on the trail.

The Maah Daah Hey's remote location and formidable length make solo missions difficult. But you can cruise unencumbered by joining one of Escape's trips. Guides will lead you between prestocked camps, shuttle your gear, and even tune your bike each night, leaving you free to groove on the strangely scenic wide-open spaces.

Sign Up: Escape Adventures, escapeadventures.com
Length of Trip: 5 days Cost: $1,165
Best Time to Go: June, August and September