This palatial spiral staircase was so unusual the name "snail" was given to the noble family who built it.

The prototype for all Nazi concentration camps.

The footprint of a frustrated devil in Munich's Cathedral.

Golden cobblestones remember a time when this small alley was used to avoid having to give a Nazi salute.

The history and future of cannabis.

Spain's unique Mosque-Cathedral has been a place of worship for both Muslims and Christians throughout its history.

Single runway interrupted by a busy road that cuts across its middle.

Catalonia Tradition: Beating the hollow Christmas log until it defecates in your fireplace.

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

Turntable anonymously received orphans, alms, and groceries.

The 2,000-year-old Roman columns are hidden within Barcelona's Gothic Quarter.

A stately palace has been converted into the world's largest cannabis museum.

An unusual stroll through gentlemen's erotica demonstrates that pornography is timeless.

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

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

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

This sweet-toothed bear searching for snacks has been a symbol of Madrid for decades.

An ancient Egyptian temple in the middle of Madrid, Spain.

Giant topiary dog once played a role in a terrorist bomb plot.

This massive fiberglass Gulliver turns every visitor into a Lilliputian.

An Irish town has built a statue to a silent film actor simply thanks to the holidays he once spent there.

Dublin's most modern, visually spectacular bridge is modeled after Ireland's national emblem.

A strange egg in a mucky bog of western Ireland marks the spot of an aviation milestone.

The modern birthplace of Irish freedom.