High atop the Eiffel Tower is a small apartment built exclusively to entertain the science elite and make the rest of Paris jealous.

A little-known subterranean street runs under some of the best-known buildings in Chicago's River North.

Hot Doug's "Hot Dog" Stand.

A century-old network of freight tunnels underneath the city's historic business district.

The final resting place of up to 6,000 Confederate soldiers, the largest mass grave in the Western Hemisphere.

One of the last functioning antique elevators in Chicago.

A chance to follow in the footsteps of the word's most legendary animator.

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

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

These pretty kitties killed and ate as many as 135 railway workers.

This alley in downtown Chicago held the bodies of over 600 people after the fateful Iroquois Theatre fire.

A speakeasy takes on Chicago's drinking culture.

Four glass boxes hover over 1,000 feet in the air to give visitors an unparalleled view of Chicago.

This shop for all your super spy needs hides an educational secret.

No one knows how many bodies are in this vault in a Chicago public park.

A Japanese temple, old German townhouses, and public chess tables offer a peaceful escape from the bustle of the North Side.

A hot dog stand where the heads are just as hot as the dogs.

This whimsical Oz-themed park had a wonderful impact on the surrounding neighborhood.

This eerily well-preserved coal town was saved from destruction by a Sean Connery movie.

This former mining hub holds a surprising abundance of undisturbed relics from the Old West.

Abandoned businesses, homes, and rusted cars are all that remains of this stopover town.

Inside this discotheque resides a unique memorial dedicated to one club-goers favorite pet.

Remnants of a cone-shaped Nazi bomb shelter.

The remains of three Luftwaffe launch pads designed for manned anti-aircraft missiles.