An underground magnet for ever-changing street art.

20,000 pieces in a Frank Gehry-designed building.

This unique structure in suburban Austin is made up entirely of other people's castaways, and constantly changing.

A Texas museum filled with Broncos and Betties.

The installation’s official name, “You Who Are Getting Obliterated in the Dancing Swarm of Fireflies,” says it all.

This modern antique shop is a museum for 1980's Saturday morning cartoon culture.

A museum dedicated to the history and exploration of both popular music and science fiction.

Enigmatic bug-like sculptures mystify drivers along a Swedish highway.

An enigmatic modern marker left next to a historic Roman site.

The artist behind this historical depiction of transportation remains a mystery.

Thousands of mounted insects, and some live ones, hide within an otherwise ordinary shopping mall.

A serene garden path lined with 36 haiku stamped into clay stones.

Life-sized sculpture of a blue whale made of hand-recycled plastic trash.

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

The narrowest street in Paris.

The tradition of open-air secondhand and antiquarian bookselling in Paris dates back to the Renaissance.

A maze of underground tunnels beneath one of the most beautiful forts in Serbia.

It leads to a former hospital’s old root cellar.

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

This memorial honors thousands of enslaved Africans and their descendants who died in colonial New York.

A beautiful and abandoned New York subway station from 1904, complete with chandelier.

Hidden behind a wall for decades, this masonic lodge was only rediscovered during renovations.

The “Sistine Chapel” of the Middle Ages merges 11th-century science and religion in wondrous hues.

A giant Troll lurks under one of Seattle's oldest bridges.