A multi-storied adobe complex has been inhabited for more than a thousand years.

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

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

The ruins of this abandoned fort now stand as a picturesque reminder of America's march West.

Twice a year, visitors can tour the desolate site that birthed the Atomic Age.

The official atomic museum of the United States explores the explosive and productive history of a much maligned energy source.

New York City's smallest piece of private property.

Bronze statue marks the spinach capital of the world.

Tribute to the famous Notre Dame football coach who died in a plane crash.

The house where the famed outlaw was shot by a dirty coward is now a museum to the criminal's legacy.

Over 600 vacuum cleaners stack the shelves of what may be the cleanest museum in America.

Thousands of small machines line the shelves of this personal collection which definitely delivers on its name.

The Bucyrus-Erie model 1850B electric shovel, or "Big Brutus," the largest existing electric shovel in the world.

This ostentatious Italianate palace of an Oklahoma billionaire is filled with several themed mini-museums.

The highest point in Oklahoma used to be a lawless outlaw's paradise.

This historic folk art garden contains a nightmare tower that claims to be the world's largest concrete totem pole.

Nature's biggest mammal swims in landlocked Oklahoma.

A whimsical tower with a spiral staircase, inspired by the Space Age and the Möbius strip.

This pseudo-steampunk weapons facility is the world's largest wood and glue structure, and packs quite a wallop.

A Texas-sized particle collider that was abandoned due to its Texas-sized budget.

The world's second-longest burning light bulb.

A modernist landscape of water and sci-fi concrete.

An emerald-green grotto just a short trip from Austin.

The largest self-built castle in the U.S., six decades in the making.