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

American involvement in World War I officially ended in 1921 in New Jersey, three years late and thousands of miles from the battlefield.

Rusting away on the edge of New Jersey are the remains of a Cold War missile launch site.

Step into Monet's world at this fine-dining restaurant in the middle of a New Jersey sculpture park.

Now abandoned, the first public health hospital in the U.S. saw more than one million immigrants from around the world.

Hidden in plain sight on the Hudson River is an abandoned train station where nature has taken over.

Eight feet in diameter and more than 24 feet around.

In this case, 'zero' marks the spot where the iconic Old Spanish Trail ends.

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

An 18th-century Spanish watchtower made entirely of seashell and concrete.

A museum befitting the city responsible for supplying the majority of the world's LSD.

A giant light 13 feet high shines near Thomas Edison's old Menlo Park lab.

This tiny New Jersey village has lived many lives but seems determined to remain a ghost town.

Seven people are buried in the middle of what's now a movie theater parking lot.

Clap your hands at the base of the pyramid, and the song of a sacred Mayan bird will echo through the air.

A haunting collection of the vanished and disappearing natural world.

The very center of Paris is surrounded by a bevy of strange good luck rituals.

The oldest stone house in Paris was built by its most famous alchemist.

France's most famous cemetery, with some of its most curious tombs.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

The gloomy ruins that inspired Bram Stoker to bring Dracula to life.

This Delaware River bridge is emblazoned with a catty slogan from a more prosperous time.

Scattered throughout London are ancient remnants of the city's former bounding wall.

One part local history, 99 parts gruesome haunted house.