Two men built this castle on the Florida coast as an artistic “landscape sculpture.”

A tribute to Ponce de Leon's supposed quest for eternal youth.

Arrr! The most authentic collection of pirate artifacts in the world... matey.

America's Most Wanted's set resides in this tribute to the history of crime and punishment.

An overlooked memorial honoring the local Washington residents who died in World War I.

While most wind tunnels test scale models, the "Cave of Winds" was large enough for actual airplanes.

Look closely and you’ll notice that the color changes a third of the way up the tower.

Those with a sharp eye can find the hidden image of a German Shepherd on the memorial's Mural Wall.

The actual model from the original "Star Trek" series is now on display at the National Air and Space Museum.

Home to items never before seen by the public.

Though the case is scorched and the buttons half-melted, this hardy handheld gaming device can still run a game of Tetris.

The home of aviation trailblazers, in a remote corner of the big city.

This mysterious marker puzzles pedestrians and infuriates geographers.

A dark patch of the ceiling at Grand Central Terminal which was not restored is still stained brown by tobacco.

This historic address is home to the beloved ball and is an almost totally empty building among the most expensive real estate in the world.

A bit of retro transportation flair preserved in the world's largest department store.

Nondescript elevator doors open to reveal a stunning, surreal world.

Nikola Tesla's former home contains an homage hidden from plain sight.

The original toys that inspired the beloved children's stories are on display at the New York Public Library.

This whimsical group of statues is a favorite of children who love to climb all over Lewis Carroll's beloved characters.

Whisper secrets in a busy station only to be heard on the other side of this acoustic arch.

An artificial tree in the University of Connecticut greenhouses holds a collection of orchids, mosses, and other tropical epiphytic plants.

A statue commemorating a 16-year old girl's nighttime ride to raise a militia against attacking British troops.

Celebrating an art form with a collection of puppets from all over the world.