This mysterious runestone embedded in a church wall is linked to the medieval cult of Saint Erik.

Ancient burial grounds of the wealthy.

A musical instrument played by the sea.

The prototype for all Nazi concentration camps.

Go surfing on this urban wave, "hacked" by local surfers.

Amidst medieval and baroque buildings, five human-sized gherkins stand tall.

Ugly 18th-century dwarf statues living in a perfectly landscaped Austrian garden.

Each year, Germany's "City of Dragons" slays the world's largest walking robot.

A quaint Russian village in the middle of a German metropolis.

Metro station with a claim to rock n' roll fame.

A monument to the three wars that led to German unification towers within a Berlin traffic circle.

An early 20th-century bullring converted into a modern shopping center.

The oldest giants in Catalonia are now displayed in a 14th-century Gothic church.

A cemetery in Barcelona's Poblenou district is home to this touching funerary statue, which depicts death in the form of a winged skeleton.

The unexpectedly beloved remnants of a controversial thermal power plant.

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

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

This stunning iron gate designed by Modernist architect Antoni Gaudí is filled with mythic symbolism.

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

Inside the small garden of two mid-century apartment buildings stands a centuries-old bell tower, separated from its original church and hidden from view.

The "Prussian Versailles" that is as glorious today as when it was built.

These medieval skyscrapers dominate the skyline of this small Tuscan town.

This bronze boar's snout has been rubbed to a golden sheen by visitors seeking good fortune.

The oldest church in Mantua was buried for centuries under the facades of other structures.