This 18th-century folly is one of Europe's rare "garden mosques."

The castle was reconstructed to fit Kaiser Wilhelm II's romanticized vision of the Middle Ages.

A famed artist's inspiring work of peace and tolerance.

This German bone house contains the remains of some 20,000 souls.

The oldest Jewish cemetery in Europe survived Hitler's Germany.

World's largest barrel containing an inn.

This medieval castle overlooking the Elzbach river looks just like it did hundreds of years ago.

This temple to the sturm and drang of Richard Wagner contains a dragon's cave and reptile zoo full of living "dragons."

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

This "floating railway" is one of the world's oldest monorail systems.

A Nazi concentration camp and Anne Frank's place of death.

The last bastion of Roman presence north of the Alps looms over a German town.

The birthplace of Karl Marx is now a museum dedicated to the communist revolutionary's life and work.

A university observatory dome painted to resemble the beloved 'Star Wars' droid.

A tiny chapel clings to a precipice above Germany’s gemstone capital.

A spitting ode to a German serial killer.

A stunning gilt bronze relief denounced by Hitler as "degenerate art"—even though it was dedicated to the Nazi leader.

Böttcherstraße's bells, extolling Nordic virtues and the great conquerors of the world.

This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.

The artist and his brother are buried in a landscape straight out of a van Gogh painting.

This small red school was where Germany signed their surrender during WWII.

A former ironworks that was the first UNESCO industrial site.

The final resting place of the famed German pilot, the "Red Baron."

A rare water-powered funicular, it uses a huge tank of water and gravity to do its work.