A breathtaking viewing platform over the Alps.

The world's oldest known salt mine.

Op-art architecture designed for happiness.

These abandoned Cold War-era bunkers are now a designated refuge for endangered bat species.

An ornate sculpture of an ox in repose marks the former entrance to Nuremberg's medieval meat market, which was destroyed during World War II.

The final resting place of one of Germany's most accomplished Renaissance men.

This strange sculpture depicts a giant nightmare hare crushing a man to death beneath its colossal bulk.

This massive statue is the personification of Bavaria and the first colossal statue of the modern period composed of bronze.

Named after the German word for "a longingness to travel," this park brings together thousands of city and street signs from around the world.

A preserved Nazi labor camp now has a Holocaust museum on site and memorials to the thousands that died while imprisoned at the camp.

The oldest residential street in Europe also features an optical illusion.

Tiny castle in the middle of the Rhine made you pay to pass.

Art historians have debated the identity of this medieval stone rider since the 19th century.

A small but immensely extravagant palace built by the "Night King."

Bizarre lunar-like landscape with thousands of large stone "hoodoos."

The fifth-longest natural arch in the world, and the longest outside China.

The picturesque birthplace of Icelandic democracy is drenched in the blood of its brutal past.

This valley of hot springs and boiling mud pots is home to the record-holding "Geysir," which originated the English word.

If a glacial river suddenly diving into a sheer chasm via a dramatic, multi-stage waterfall isn't peak Iceland, it's certainly close.

The most powerful waterfall in all of Europe.

This tumultuous Icelandic lava field looks so alien European researchers want to use it as a stand-in for Mars.

Iceland's largest lagoon is home to stunning multi-colored icebergs.

A desert ghost town—occupied for only 12 years—was once home to more than 500 silver mines.

The set location for a 1987 cult classic draws international film buffs to the middle of the Mojave Desert.