Macabre astrological automaton clock dating to the late 1400s.

Tiny memorials honor individual victims of the Holocaust.

Jesus' footprints and the first catacombs in the world.

Rome's semi-secret peephole vista is also a former Crusader stronghold.

This bustling Italian plaza is built on the ruins of an ancient Roman amphitheater.

Fortified medieval tower house with lovely roof garden.

The last moments of the ill-fated Pompeiians, frozen forever in plaster.

The walls and streets of the ancient city are peppered with penises.

A copy of the famous statue can be found in this Florence piazza, along with one of the most breathtaking views of the city below.

Five candy-colored villages on the Italian Riviera.

A lover's walk between hilltop towns, decorated with graffiti love notes.

Thousands of coffin-like pillars make up this controversial Holocaust memorial.

Daily jousts and dancing barrel makers in Munich's mechanical clock.

The fairy tale castle of the "fairy-tale king."

The fully functional, submerged Vanuatu Post Office is definitely one of a kind.

Famously misunderstood wonder of the ancient world

This 1,300 year old monastery built atop a single rock was once only accessible depending on the whims of the tide.

The world's largest reflecting pool is just two centimeters deep.

This natural Icelandic fissure allows divers to swim right between two volatile tectonic plates.

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.

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

This eye-popping Icelandic crater lake is surrounded by red volcanic rock.

Medicinal spa created with the discharge from a geothermal energy plant.