The sanctuary holds what was once believed to be the saint's incorruptible tongue.

A church of bones, decorated with 40,000 human skeletons.

This Italian foot path winds through the mountains via 52 individual tunnels.

This massive subterranean fissure is known as the "underground Grand Canyon."

Castle and secret tunnel withstood a siege until its owner was killed by the Holy Roman Empire, while sitting on the toilet.

A whimsical bridge adorned with decorative dragons.

The first spinning jail built in the United States is the only one that still turns.

An abandoned munitions factory with a shot tower continues to wage war on the surrounding environment.

A castle built by an eccentric medieval enthusiast in rural Ohio.

A hidden network of subterranean passageways lies tangled beneath Indianapolis' bustling City Market.

The farm where one of America's greatest leaders was raised is now a well-appointed landmark.

A turn-of-the-century architectural marvel built on healing mineral springs and salt licks.

After a water tower painting was accused of being an ad, a simple fix was made that gave the city a motto.

This railroad overpass is said to be home to a murderous goat-man whose very legend has led to very real deaths.

Ruined pieces of stone and a swimming pool are all that remain of an amusement park swept away by a flood.

This former tuberculosis research hospital endeavored to cure the dreaded disease with fresh air and positive attitudes.

This 19th century mansion façade adorned with immigrant patriotism is a symbol of Louisville’s history.

This abandoned cemetery has a dark past of bodies buried over bodies.

The largest cemetery in Louisville is the final resting place of Col. Sanders and Muhammad Ali.

The grave of the iconic Kentucky Fried Chicken mascot features a bust of the man behind the goatee.

This candy shop has been serving up sweets to the Louisville area since the 1850s.

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

The only building in Louisville (hopefully) that contains two ancient holy skeletons.

Vienna's giant wonder wheel had a starring role in one of the greatest noir movies of all time.