This incredible college library is a visual masterpiece of mosaic art. It also looks kind of like a giant boombox.

The only castle in North America to ever house European sovereigns.

The famous artist couple lived and worked here, in two different houses separated by a bridge.

These sacred Mesoamerican ruins feature peculiar petroglyphs hidden in the stones.

This staircase full of Mayan hieroglyphics is perhaps the largest single text in the world.

A formerly glacier-tipped volcano that inspired none other than Jules Verne.

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

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

This beautiful, historic church looks like something out of a simpler past.

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

This stunning concert hall has become a symbol of Iceland's national recovery.

An encyclopedic collection of mammal penises.

One of the tallest buildings in Iceland, and perhaps, the most visually impressive.

Famously misunderstood wonder of the ancient world

A wall of chewing gum moonlights as collective art.

A museum dedicated to the history and exploration of both popular music and science fiction.

A giant Troll lurks under one of Seattle's oldest bridges.

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

Macabre astrological automaton clock dating to the late 1400s.

Largest cave system in Africa.

The largest prehistoric ruins south of the Sahara, once a powerful center of international trade.

The world's largest impact crater is mainly eroded but still remembers the planet's violent history.

Home to some of the oldest hominid fossils ever found.

Caves that can't seem to quit producing the remains of prehistoric humans.