A Winnebago Tribe collection featuring arrowheads, artwork, and a mysterious rock carving.

A roadside collection of over-sized iron creations that are a bit more macabre than most.

This picturesque Umbrian city has a subterranean side that has long remained hidden.

A cavernous three-story, 43,800-square-foot basement that was forgotten about for 60 years.

Hidden in a grotto 26 feet below Nottingham's oldest hotel, this stylish subterranean drinking den is notoriously hard to find.

A restored 1920s cascade stairway provides one of the best views of Oakland's Lake Merritt.

A proto micro-nation sometimes populated by artists, surrounded on all sides by a Utah most barren.

A sculpture for the sun and stars, created by Nancy Holt.

A quirky old tree covered in tokens, cans, and bottles of wishes.

This century-old roadside attraction is full of bizarre rock formations.

This futuristically sylvan church is a glass-enclosed marvel of modern architecture.

A fashion designer's dazzling world of Japanese collectibles is hidden in a warehouse downtown.

A beloved carnival gets a modern makeover in Los Angeles.

A favorite haunt of dinosaur loving children and hallucinogen loving hippies alike.

A famous alternative culture epicenter and where Joplin serenaded young hippies.

Nuclear waste dump site now an environmental sanctuary.

Experience Larry Spring's self-taught "common sense" laws of physics.

Treehouse motel and treehouse-building school.

Located on 420 acres in the high desert, this spiritual center is dedicated to the "science of the future."

A world-class observatory in the California desert.

Semi-recognized center of the world, with many oddities.

Home to the infamous "Typhoid Mary" and the worst loss of life in New York's history prior to September 11, 2001.

Vortex-shaped aquarium hosts Europe's largest school of piranhas and other ocean creatures.

Danish observation tower designed to look like a giant beer bottle.