One of the oldest active carousels in the country—but it might be missed by all but the keenest-eyed boardwalk strollers.

This building at the south end of the boardwalk was once home to the U.S. Life-Saving Service and the U.S. Coast Guard before being rescued itself.

The land is home to swimming ponies and a legendary 18th-century treasure.

WWII-era bunkers are hidden under the beaches of this picturesque park, which is still scattered with wartime watchtowers. .

Step inside Lucy, the world's largest "elephant."

A granite monument honors a beloved World War II canine mascot.

These unassuming lighthouses have seen the first reading of the Pledge of Allegiance, the first wireless transmission, and more than one mystery.

The famous bell was secreted away and hidden in a church in Allentown during the British occupation of Philadelphia.

The internal railway of one of the biggest steel plants in America has been transformed into a linear park with unique industrial views.

A pride of the state, this working museum crafts pottery mosaics in the style of Pennsylvania's earliest European settlers.

This elaborate towering structure was once famed for its revolutionary height.

World's first "penitentiary," meant to be humane, drove men insane.

Pulled from the rubble of one of the worst modern tragedies, a steel crossbeam became a symbol of hope for New Yorkers.

The last living thing to come out of the rubble after 9/11 is now a symbol of hope and resilience.

This sculpture by artist Fritz Keonig survived the 9/11 attacks and now stands as a monument to the victims.

A labor of love built by local hang-gliding enthusiasts, this ideal launch spot was outlawed by the authorities and has since been largely abandoned.

The fanciest public restroom in New York City boasts fresh flowers, art, and a classical music soundtrack.

Elevated freight railway turned wildly successful urban park.

This 1830s store is believed to be the site of Harriet Tubman's first stand.

The stone marker that Mason and Dixon placed at the eastern end of the famous north-south border they surveyed.

The third tallest lighthouse in America once guided author Stephen Crane to safety.

A building so large that it has its own weather.

Disney World's very first waterpark is now an abandoned ruin being reclaimed by the swamp.

Disney's abandoned animal island is now an overgrown ruin that was almost the coolest attraction ever.