Curious crustaceans support an obelisk from ancient Egypt that now stands in modern-day Central Park.

An uber-secure, windowless tower of doom in the center of Manhattan is an NSA spyscraper.

A pedestrian island in the middle of world-famous Times Square emits a strange (and purposeful) humming noise.

This unmarked and unloved Manhattan subway grate created one of the most iconic images in American cinema.

Mysterious 500-year-old tapestries depict a unicorn hunt.

More gold than anywhere else, ever.

New York City's smallest piece of private property.

The "Seinfeld" diner.

The world’s oldest and biggest bookstore stocking only mystery, crime fiction, espionage, and thrillers.

A treasure trove of artifacts, books, and artwork from the "golden age" of exploration.

The 44,000-ton aircraft carrier was purposely sunk to create an artificial reef teeming with life.

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

A violent name for a violent volcano.

Rare signs of the former Soviet Union in the Caribbean, though not where you'd expect them.

This stone commemorates the island's launch into international aviation.

A Barbados crypt where it's said that the coffins refuse to stay put.

This popular tourist cave was ignored for almost 200 years before being mined into an attraction.

Where Saint-Martin ends and Sint Maarten begins (or vice versa).

As one of the world's largest hydroelectric dams this plant took two countries to get built.

This living labyrinth made entirely of thorns is filled with art.

The mouldering manses of wealthy colonials still pock the streets of a Curaçao neighborhood.

The remnants of an abandoned, 19th-century gold mill along Aruba's rugged northeastern coast.

This mountaintop lake bubbles and steams in a perpetual boil, thanks to its direct link to the Earth's interior.

Thermal springs underneath the seabed provide the heat and bubbles for these beachside natural hot tubs.