Florida's first suspension bridge.

The only Florida state park with publicly accessible caves.

This now-deactivated naval base defended the Florida coast for centuries.

A local landmark with generations of spraypainted messages, and more being added each day.

The highest point in Florida is still the lowest high point in the country.

Part of a highway network meant to connect Miami to Montreal, this 10-mile stretch of road made from red bricks is still around 100 years later.

Rumored to be the famed pirate's lookout tower, this historic stone structure is now just watching for tourists.

This huge pile of volcanic boulders hides a stunning network of secret grottoes.

The world's longest known cave system.

Eight rare Corvettes are swallowed up by a sinkhole in Kentucky's National Corvette Museum.

You have to love a museum with a truly dedicated focus. A focus on Superman, for example.

A 22-foot stainless steel quilting needle pays tribute to a local connection to fiber arts.

A collection of outdoor art by renowned muralist Robert Dafford depicts the history of a flooded city.

The last place in Florida where wild bison roam

The only subway station in the city that still makes use of gap fillers.

With a history dating back to Victorian times, this architectural gem is a rare New York tourist haunt worth visiting.

Long the exclusive domain of birds and vagabonds, this little-known Central Park peninsula is open to the public once more.

This lower Manhattan bar is set up in an old bank vault that rests beneath a skyscraper that hides even more historic splendor.

Wooden pavers represent a 17th-century barrier that gave Wall Street its name.

Where now stands a 42-story condominium tower of marble, glass and steel was once the central market of New York’s slave trade.

After traveling the world, one of the last remaining fully-rigged three masted iron-hulled cargo ship in the world found its home in New York.

The home of the first American-born saint is one of the only curved buildings in New York.

Manhattan's lighthouse, erected at the insistence of the unsinkable Molly Brown.

The façade of this building looks like a bingo board, but it's really a giant clock by a famed graphic designer.