66,000 pieces of art, donated by one of the world's richest men.

Part bookstore, part café, and part forest.

Superstitious? Discover the witchy side of Mexico through its largest esoteric market.

Frida Kahlo's childhood home, now a museum of her life and works.

An island filled with hundreds of hanging, decomposing, decapitated dolls.

No one knows who's responsible for decorating this tunnel with stuffed animals, but the people love it enough to protest their removal.

According to legend, this boat-shaped henge is built over the grave of a mythic king.

This chimerical bridge/tunnel appears to dead end right into the sea.

It is said that each of the white stones in the red facade of this medieval house represents the head of a murdered Swedish noble.

Street artists transformed this abandoned industrial neighborhood into one of Europe's largest graffiti exhibitions.

Stockholm's deepest subway station is also a stunning ecological wonder.

The library's graceful rotunda is like a bibliophile's temple.

Stockholm's decidedly unique public transit system has doubled as the world's longest art gallery for decades.