Kentucky's anomalous peninsula projecting into the Mississippi River, site of legendary earthquakes and local feuds.

Locals place their offerings on this nightmarish gnarled tree so the witches won't summon another storm.

Amazing taxidermy dioramas from the 1960s in a cement building meant to look like an ice cave.

This fast-food outlet is the only space and UFO-themed McDonalds in the world.

A museum dedicated to the alleged Roswell Incident.

The second-largest cave chamber in the world was discovered in 1898 by a 16-year-old and a friend known as "Pothead."

Seemingly grown on some other world, these New Mexico rock formations look like a disused science fiction set.

The land is full of geologic eye candy, such as otherworldly spires, mushroom-shaped hoodoos, and prehistoric fossils.

Explore the largest pure gypsum deposit in the world, and go dune sledding while you're at it.

One man has carved a number of natural New Mexico caves into psychedelic sandstone temples.

An immersive environment that is part haunted house, part choose-your-own-adventure, and part jungle gym.

This large cave is a summer home to thousands of bats and has a rich history dating back to prehistoric times.

Elvis's own personal tropical hideaway.

A failed utopian experiment for British expats in the American South is now a Victorian village frozen in time.

This head-spinningly bizarre Depression-era art cave is wall-to-wall quartz and Jesus.

Mile-long cave system near Great Smoky Mountains.

More than five miles of underground passageways.

The secret city built by the Manhattan Project.

Wild lights and sound effects turn a walk through some caves into an eye-popping 1960s tourist attraction.

Enormous lake at the bottom of a unique cave system.

Eight rare Corvettes are swallowed up by a sinkhole in Kentucky's National Corvette Museum.

This grave marks the final resting place of a legendary frontiersman... unless it doesn't.

A museum that houses the world's largest collection of ventriloquism dummies.

Kentucky, Tennessee, and Virginia meet at this point in the Cumberland Gap.