The only swimming pool listed on the National Register of Historic Places is emptied and refilled each day with naturally filtered water.

A mysterious castle built as a monument to lost love.

This lush Florida island is home to the ruins of a crooked ship breaker's tiny empire.

This 140-year-old beacon off the Florida Keys marks the wreck of a Navy ship that once roamed the Caribbean hunting pirates.

A unique collection of diving equipment spanning antiquity to the present day.

This spiny beast guards an artist's village while vying for the title of largest lobster in the world.

The world's only underwater laboratory where "aquanauts" study oceanic life.

An underwater statue of Christ blesses the depths off Key Largo.

Stay in a room with a view... of the bottom of the ocean.

The famous boat that once ferried Bogart and Hepburn still floats in Key Largo after being abandoned for years.

Dedicated to the victims of one of the deadliest hurricanes to strike the United States in recorded history.

Island ghost town detailing Flagler's folly in building the Overseas Railroad.

"We Seceded Where Others Failed."

This woodland architectural installation acts as a camera obscura for the heavens.

Every plane, auto, and bicycle in this collection is kept in working order and are regularly demonstrated to the public.

An unusually designed bridge from the 1920s was built to withstand the tides and winds of Maine.

The first bridge observation tower in the U.S. offers one of the best views of Maine.

Turns out you can see the world without ever leaving Maine.

When the town wouldn't allow the fast-food behemoth to build a new restaurant, they put one inside an 1850 home.

This 19th century granite fortification is one of the most well preserved forts in New England.

The highest point in Maine is a grand gift to the state citizens that also happens to be one end of the Appalachian Trail.

Stone monument honoring a town founder has a witch-boot shaped stain and a curse to go with it.

This candy-striped tower is the farthest east you can go in the United States.

The only remaining historic maritime signal station in the United States.