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

The show pony of cave systems, Fantastic Caverns manages to live up to its name.

If there's another drive-through golf-cart bar in a bat-filled cave on top of a mountain, we don't know about it.

The world's largest man-made underground caverns offer unparalleled underwater wonders.

The "World's Largest Underground Business Complex," a 55,000,000-square-foot city underneath Missouri.

Once an ambitious nature spa, these forest ruins now provide a serene monument to failure.

The lowest point in the state of Illinois, at the confluence of the Mississippi and Ohio rivers.

Built in 1869, this now-retired structure looks more like a medieval fortress than a county lock-up.

This national park dedicated to the tallgrass prairie ecosystem still displays its military past.

The original vault that held the president's remains still stands, empty, not far from where he was finally buried.

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

The final resting place of the world's first nuclear reactor.

A replica viking ship from the Chicago World's Fair is still in dry dock in an Illinois park.

The unluckiest U-boat in the entire German fleet is now on display in a Chicago museum.

Fragments of architectural wonders from around the globe are embedded in the newspaper building's walls.

This grave in a ghost town cemetery marks the death of a witch on a day that never happened.

This elaborate Hindu temple is located in a Chicago suburb, but looks like it was transported directly from India.

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

This overgrown Illinois water park offers a whole new type of adventure.

This modest post office sits on the site of H.H. Holmes' famous murder castle.

One of the largest pieces of scientific equipment ever carried on a NASA space shuttle sits in a Chicago alley.

Built to house a chapter of the Knights Templar, this grandiose building is a relic of Freemasonry in Chicago a century ago.

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

Cemetery featuring rare glass-fronted columbarium.