This road in the Great Smoky Mountains was supposed to assuage a displaced community, but ended up a $52 million dead end.

John Hendrix predicted the creation of the "Secret City" built as part of the Manhattan Project.

A recreation of the doomed ocean liner in the middle of the Smoky Mountains.

One man has spent decades faithfully constructing this unique brick and cinderblock castle.

Knoxville’s architectural icon was the symbol of the 1982 World’s Fair, even catching the googly eye of Bart Simpson.

Better known as the "Body Farm," this unique research facility has been studying how human bodies break down since the 1980s.

The remains of one of America's first radiation testing grounds still rest ominously in a Georgia forest.

These eerie outliers of the lightning bug family glow a mysterious blue color.

The mysterious 855-foot zigzagging stone wall has been baffling people for centuries.

Visit this playground of waterfalls, caves and sinkholes.

This North Carolina museum is keeping the pinball craze alive, with a little Space Invaders on the side.

Who needs fancy modern water slides when this giant North Carolina rock works just as well?

Step back in time on this preserved 1800s farm.

One of the Cemestos prefab homes built to secretly house thousands of Manhattan Project workers.

Over 20,000 sets of spice shakers reveal the surprisingly telling history of our most basic spices.

The world's largest vertical wind tunnel.

Designed by Maya Lin, the memorial honors 41 individuals who died fighting for equal rights between 1954 and 1968.

The remains of an idyllic small town built for the film 'Big Fish' still stand around a rundown main street.

The antique barns in Cameron are not painted with your grandfather's Mail Pouch Tobacco murals.

A curious whirlpool formation supposedly capable of entangling or engulfing branches, tree trunks, or whole rafts full of hapless tourists.

One-layer pyramid in Indiana.

A museum to a cave explorer whose tragic death was a media sensation, and whose corpse became a tourist attraction.

One of Cincinnati's greatest fighters once trained at a now defunct gym in this Over-The-Rhine neighborhood.

The massive, original Colgate Clock is mounted on a defunct factory building that was once a prison.