Everyone's invited to put on a miniature concert with this world-class musical wonder.

The site of a 19th century "dream city" that almost rivaled Chicago before being swallowed by the Indiana sand dunes.

France's most famous cemetery, with some of its most curious tombs.

An unassuming store hides relics of its former life as the jazz club that hosted some of the best black performers of the 1920s and '30s.

Hot Doug's "Hot Dog" Stand.

This surprising gem is a world-class archeological museum hidden at the University of Chicago.

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

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

Rifle through images of skyscrapers, Worlds Fairs, and more in the largest public postcard repository in America.

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

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

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

The beloved home to all publications indie, erotic, and punky.

Where old school Polish Chicago and young hipster Chicago live side by side.

This historic hotel invented the chocolate brownie.

One of the few remaining relics of the meatpacking hub that made Chicago the "hog butcher to the world."

These abandoned grain silos and tunnels are an urban exploration dream.

This feline raises a friendly paw at drivers barreling toward the freeway.

A giant, Gilded Age mansion that once belonged to the beer baron of Milwaukee.

One-of-a-kind preserved ruins of an abandoned 1880s church in Chicago's Pilsen neighborhood.

Honoring Italian greats from Joe DiMaggio to Rocky Marciano.

This historic store hides a museum exhibiting a shoe-sizing x-ray machine and a pair of kicks that once belonged to the world's tallest man.

A tribute to one granddaughter's old apartment which now represents the whims of each visitor.

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