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

A Bibliophile's Dream.

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

The iconic Chicago sculpture hides a beautiful and easily overlooked plaque on the backside.

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

The twin towers in this Chicago fountain use 50 foot tall video screens to spit on people.

The palatial McDonald's that inspired Wesley Willis.

Legend has it the commander of the defenders drew a fateful line in the dirt with his sword just before the final battle.

A gorgeous garden oasis with winding paths, stone bridges, and a troubling history.

The celebrated eyesore created by starry-eyed sweethearts.

This demon atop the Notre-Dame de Paris looks utterly bored.

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

Inside this mountain lies several kilometers of breathtaking caves.

The remnants of a depressing public toilet are now a hub of ever evolving street art.

A tiny, heartwarming piece of art hiding in plain sight.

Be on the lookout for the symbolic insect all over the city.

The small bright red pillar survived the 1996 Manchester bombing virtually unscathed.

Known as the "Stairway to Heaven," this historic canal dates back to the 1700s.

This historic abandoned train station looks like a stop for ghost trains.

Tucked away in the Tower of London is the weapon once used to execute high-profile prisoners.

This pump on the bad side of Victorian London betrayed a horrifying revelation about the water supply.

The watery entrance for condemned prisoners heading to the Tower of London is still visible along the Thames.