An abandoned observatory in the middle of the Illinois prairie.

On the coast of Sardinia, a once-great mining village is finding new life as a coastal resort town.

The park that the Chicago Stockyards built.

The legacy of an unsolved, gruesome murder rests beneath the spans of this historic bridge.

Now nearly abandoned, Kaskaskia was once the capital of Illinois and one of the most important towns on the upper Mississippi.

Home of an evil witch famous within southern folklore.

During the 19th-century, this park was a vital trading fort.

This wooded grove of beautiful hand-built stone grottos is a hidden gem within a shuttered Franciscan monastery.

This former small town was destroyed not by the motor oil it sprayed the ground with but by the toxic waste that was added.

A late sculptor's last project was to turn this abandoned cement factory into a castle-themed amusement park.

Hiding behind a grocery store is a spectacular cavern carved as part of an old limestone quarry.

A notorious Route 66 eatery once frequented by Al Capone.

What was meant to be a temporary exhibit is now a permanent fixture at the St. Louis Zoo filled with beautiful birds.

Buy a token from the liquor store and you can make this beast spew flames on command.

Erosion and time have created a naturally-formed water park.

A floating museum that was sunk by a flood and left to rot in the tides.

The mysterious white squirrels of this Illinois city are treated like sacred cows.

Once one of the world's great cities, Cahokia was a place of religious worship, trade and mass human sacrifice before being mysteriously abandoned.

In the St. Francois Mountains in the Ozarks at 1,772 feet above sea level, Taum Sauk Mountain is the highest (and possibly oldest) peak in Missouri.

Giant granite rocks standing end-to-end like a train of circus elephants.

Patrick Dougherty's fantastic living tree sculptures, mind-blowing but temporary.

A subterranean haunt where wine and homemade biscottis are always on the menu.

River pirates, murderous bandits, and serial killers used this Illinois cave as their debauched hideout.

This curious headstone is labeled simply as "The Queen."