A luxurious doomsday bunker hidden beneath an unassuming Las Vegas home offers the best of subterranean suburbia.

The drama of nature in full effect in this Nevada State Park.

Dyed by iron oxide over centuries, these sandstone rocks rise thousands of feet into the sky.

Scores of vintage street lamps shine along L.A.’s Miracle Mile.

360° views of the city plus five floors of optical illusions and hands-on science.

At this Denver landmark, the meals are compulsory, the sopapillas are complimentary, and the insanity is everywhere.

An underwater city for the dead.

This naturally-sourced hot spring is now home to a clothing-optional resort.

A self-built castle made by a mysterious man.

A beautiful geyser under environmental threat.

A 30-acre garden inspired by the principles of modern physics.

A Jenga-style cylindrical tower of books that appears to go on forever.

A breathtaking array of ancient Pueblo structures and artifacts counterintuitively preserved by neglect.

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

The most iconic structure in Scotland has been home to bishops, colonels, and Sean Connery characters.

The first declared National Monument in the United States.

Architectureal fantasy quarter of Rome.

Where manatees are the snowbird vacationers in these balmy Florida springs.

A beautiful 62-acre Catholic shrine and botanical garden.

This hidden Art Nouveau courtyard is an opulent feast for the eyes.

Rainbow-hued local gem in Venice.

The sign at the garden gate reads: "These Plants Can Kill."

The fairy tale castle of the "fairy-tale king."

Medicinal spa created with the discharge from a geothermal energy plant.