Teddy Roosevelt described the broken landscape of the less-visited Badlands of North Dakota as a "grim fairyland." On the 96-mile Maah Daah Hey Trail (nps.gov/archive/thro), from the south unit of his namesake park to the north unit, you'll understand why. It's a moonscape of pinnacles, mounds, and crumbling cliffs. Pass within yards of buffalo and yelping prairie dogs, and sleep at any of the trail's three remote campgrounds.