The remains of Crystal Palace Great Exhibition of 1851.

These delicate buggers are some of the rarest fossils that have bubbled up from the Tar Pits.

Mysteriously stacked storefront paths give this medieval British town an iconic style like none other.

Every equinox this Maya pyramid puts on a spooky ancient light show.

A cluttered and astounding collection of antiquities and curiosities.

A Parisian cemetery where the elite and artistic are interred beneath an eccentric collection of tombs.

Ride the subways of yesteryear.

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

A once grand hotel is being retaken by the wilderness it once capitalized on.

Home to the largest urban bat colony in North America, estimated at 1.5 million bats.

1,001 carved statues of the Buddhist God of Mercy, each with a unique face.

A museum dedicated to exhibiting remarkable outsider art.

Frank Lloyd Wright's most iconic home dangles over a Pennsylvania waterfall.

The celebrated eyesore created by starry-eyed sweethearts.

A 1,215-foot tunnel transports pedestrians beneath the River Thames.

Strange red rock formations that have been attributed to a higher power for hundreds of years.

A bizarre roadside attraction and the first instance of miniature golf in the world.

A huge musical sculpture and other art installations on the National Oceanic and Atmospheric Administration grounds.

A scandalous Art Nouveau collaboration that set Paris all atwitter at the turn of the century.

A museum on the history of Paris, including a set of Napoleon's toiletries, Proust's room, and relics of the Revolution.

Tiki luxury on Nob Hill.

A popular swimming hole that hides one of America's most deadly diving spots.

A three-story copper skybridge connects two Manhattan buildings with Art Deco luxury.

Hear the quietest sound from across the dome.