Grand Canyon Caverns Suite—Peach Springs, Arizona

True, you’ll feel like Fred Flintstone when you first open your eyes in the Grand Canyon Caverns Cave Suite—and  find your seventy-foot ceiling roofed with rock some sixty-five million years old. Perhaps you’ve even brought along a pair of dinosaur-pattern pajamas to take the nip out of the underground’s perpetually crisp fifty-six-degree air. Grand Canyon Caverns is the king of road-side wonders surviving along the western section of old Route 66. Its hidden largesse was discovered in 1927…

The Cave Suite is touted as the darkest and quietest motel room in the world, but the amount of silence and isolation experienced is up to the individual. The room—which books for $800 a night for two, plus an additional $100 for every additional person up to six—truly is a sweet hideaway nestled at the center of the earth.