Once at the center of U.S. finance, the historic Trading Room was meticulously recreated piece by piece and rebuilt in the Art Institute.

At Chicago's revered Field Museum, visitors are invited to learn about and literally explore DNA.

To find the "unicorns of the deep" you've got to go downstairs.

This awkward aquarium sculpture is one of the strangest statues in Chicago.

These chunky stone towers out in Lake Michigan are the key to Chicago’s drinking water.

Chicago's Navy Pier on Lake Michigan was a training hub for aircraft carrier pilots during WWII.

A 400-foot-tall tall map of Chicago makes this once-ignored building stand out.

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

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

This unmarked and unloved Manhattan subway grate created one of the most iconic images in American cinema.

If it hadn't been caught in time, a flaw in the design of this Manhattan skyscraper could have led to its collapse.

A stack of stones steeped in Irish folklore, much like the hero they're connected to, hide in plain sight.

North Carolina's finest examples of Native American pictographs have survived for 5,000 years.

This North Carolina museum is keeping the pinball craze alive, with a little Space Invaders on the side.

It is locally loved and ridiculed for literally looking like poop.

It took years to decode its mysterious messages.

A wall of chewing gum moonlights as collective art.

This modest marker near Notre Dame identifies the very center of Paris.

The celebrated eyesore created by starry-eyed sweethearts.

This emotive sculpture was originally created for the 1878 World's Fair.

A beautiful Victorian statue shows France's enduring love of the rhinoceros.

Remains of the artificial harbours invented for the Allied invasion of Normandy can still be seen at sea.

The fierce beast perches atop a pedestal marking where the historic City of London gates once stood.

A plaque is all that remains of a lost Oxford transport hub.