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

Hidden in plain sight on a pair of Manhattan subway tunnels are a pair of public instruments that sing to each other.

A tunnel once abandoned now thrives with graffiti art as an off-limits makeshift gallery.

Hidden in an ordinary Midtown building is a one-room museum dedicated to the greatest escape artist.

A room in New York City that contains 250 cubic yards of dirt worth a million dollars.

The oldest surviving bridge in New York City, which reopened to pedestrians in 2015.

More gold than anywhere else, ever.

A hands-on traveling collection of the innovative devices of yesteryear.

A DIY art gallery/music venue/lecture hall dedicated to video game culture.

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

A Pythagorean funhouse that tries, successfully, to prove that math is the coolest thing ever.

The earliest known map to show America, discovered by accident at a Paris bookshop.

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

One of Antoni Gaudí's most classic buildings is well-known for its "dragon-back" design.

Three bridges and one giant canyon make up this fantastic Spanish settlement.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

A strange egg in a mucky bog of western Ireland marks the spot of an aviation milestone.

Achill's most recently abandoned village dates back to to the Age of Enlightenment.

To literally keep their waste out of their own backyards, the citizens of this English city built an impressive sewer system that is still in use today.

One fisherman has used his love of pebbles and shore to create a crazy garden of rocky art.

The natural history museum displaying the British bird collections and dioramas of Edward Booth, free of charge.

This tunnel entrance is built to resemble a grand castle but no one is quite sure why.

Decrepit Victorian public lift is a white-knuckle ride.

The spot where three Protestant clergymen were burned at the stake during the reign of "Bloody Mary."