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

This NASA test station is home to some of the world’s largest and most powerful space environment simulation facilities.

Funded by John D. Rockefeller, this is one of the earliest, and most beautiful, shopping arcades in America.

Take a drunken tour inside the world's largest known geode.

A sealed test tube said to hold Thomas Edison's dying breath was given to the inventor's friend and mentee, Henry Ford.

An ever-evolving wall of graffiti art off East Liberty Street.

Near the ruins of a Civil War coastal fortress lies the only known African refugee cemetery in the United States.

Visitors are welcome to enter this lush Key West sanctuary to entertain its plethora of rescued parrots.

A monument celebrating the idea of reaching inaccessible places.

Florida's oldest bar was once a morgue, complete with a hanging tree and gravestones.

These remote Florida islands have a history of sea turtles and sunken treasures, and one of the world's largest coastal brick fortresses.

A frozen relic of Seattle's hydroelectric boom is now a teaching facility for future engineers.

This popular bar has been blurring the line between normal and edgy for more than 75 years.

A wall of chewing gum moonlights as collective art.

This nine-story building can be played like an instrument.

The scene of the largest surrender of Confederate troops at the end of the American Civil War.

Legend says a primate-like cryptid prowls this otherworldy sliver of the Louisiana bayou.

Hidden inside this Arizona fast food franchise is an in-depth exhibit on the famed WWII counterintelligence program.

The longest living non-clonal organisms on Earth.

A mysterious monument meant to be a guide into "an Age of Reason" was destroyed after an apparent bombing.

An abandoned boat that's been stranded mysteriously for decades.

A decaying garage hidden amid the dense forest is all that remains of a once-prosperous dairy farm.

A preserved stretch of ancient fossilized trees with an impressive gem collection to boot.

Despite what scientists think, the town still says this is an extraterrestrial rock.