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

Dine on food tied to Viking history and legend at this subterranean Stockholm spot.

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

The world's first ice hotel is still one of the most elaborate and beautiful.

Did he come up with a theory of cosmic-ray showers while sitting in this bath?

The final resting place of one of the brightest physicists of the 20th century.

This pair of gilded girls atop an Art Deco building in Copenhagen were built to function as a weather indicator.

This bridge's unique architecture honors nautical heritage and encourages self-awareness.

The world's first combination ski slope and power plant.

Bored potato-guarding Nazis etched their thoughts onto a brick storage building in Copenhagen's Meatpacking District.

The old observatory in Copenhagen has a spiral corridor used as a racetrack.

The de facto symbol of Copenhagen is this bronze fairytale which cannot seem to keep its head for very long.

This sublime architectural marvel is a rare example of an expressionist church.

Hans Christian Andersen for the postmodern world.

A crucified and bearded female saint.

Increasingly decayed figures stand as a powerful reminder of the human costs of Czech Communism.

A bus with a butt and biceps to put Olympic athletes to shame.

A bust of Franz Kafka spins in pieces, reflecting the writer's inner torment.

A controversial artwork draws attention to the dark history of Prague's "Suicide Bridge."

An existential riddle in the world's largest ancient castle.

The palace window through which Protestant nobles flung two Catholic regents, thus sparking the Thirty Years' War.

A former top secret nuclear fallout shelter now operates like a hotel stuck in the Cold War.

Two stunning 17th-century libraries and a cabinet of curiosities.

In the hometown of the Catholic saint and Nobel Peace Prize winner, a memorial dedicated to her legacy.