Constructed along the shores of Lake Zurich, this pavilion is a walk-through work of art.

An opulent monument built for a duke who donated his entire fortune to the city of Geneva.

Some 80,000 Delft Blue tiles line the inside of this Amsterdam walkway.

An ancient passage filled with stalls selling used books, once frequented by Vincent Van Gogh.

A bloody history is captured in this former prison turned museum.

The sacred shrine of the Yazidis.

An ancient sanctuary that has long been a holy site for the Chaldean Christian Church.

An ancient fortified mound raised over the millennia from settlements built one on top of the other.

A musical instrument played by the sea.

The medieval ferry service has been going strong since the 14th century.

Now harmless, this looming post struck fear into the heart of medieval troublemakers.

A chain of 16 wondrous lakes formed as a result of the gradual dissolution of soluble layers of bedrock.

Thousands of flowers create enchanting pink tunnels over the city streets.

Statues of a fire-breather, a clown, and a whole performing troupe celebrate Luxembourg's creative side.

An expansive complex of subterranean tunnels is all that remains of one of Europe's most formidable medieval fortresses.

This magenta statue commemorates the legendary marriage between a mermaid and the city's founder.

Two standing giants remain as a tribute to Luxembourg's metallurgical past.

A rare chance to ride one of the few continuous elevators still in operation.

Fantastic views and thousands of love locks.

Thousands of tourists and residents in Cologne affix "love padlocks" on the Hohenzollernbrücke Bridge to symbolize their affections.

This small condiment museum makes all manner of mustards with a 200-year-old mill.

The largest mosque in Germany.

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

In the summer of 1957, a massive architectural exhibition showed off the future of urban living in this German neighborhood.