A giant concrete orb in far north Iceland marks the ever-shifting boundary.

The Arctic Circle runs through this isolated spot north of Iceland.

This scenic Icelandic lava flow is named for a pair of Berserkers who were murdered, according to a famous Saga.

Three million year old fossils are exposed for all to see on this Icelandic shore.

A modern Nordic Pompeii on the Icelandic island of Heimaey.

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

The most powerful waterfall in all of Europe.

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

A stratovolcano located in the south of Iceland, with a long history of charted activity and a rich mythology attached.

Hundreds of stone stairs and a winding medieval bridge connect this haunting Spanish island to the mainland.

The 43-mile route crosses through six islands with gorgeous views of the Seto Inland Sea.

This short bridge is the only thing connecting a tiny Irish island to the mainland.

Resting in the middle of an Austrian river, this sci-fi "island" lets people cross in neon style.

Remote Honduran Islands with a colorful history.

This incredibly diverse research station is one of the largest tropical botanical gardens in the world.

This collection of historical artifacts and tropical wildlife waits just beneath the surface of the water.

Only gap in the 30,000-mile span of roads called the Pan-American Highway.

One Costa Rican island is so beset by illegal shark poachers that the local rangers have built an entire bridge with their confiscated gear .

These Honduran caves earned their magical nickname thanks to reflective bone deposits.

The youngest volcano in Central America.

A no-frills, DIY nature preserve manned by a U.S. expat who has dedicated his life to turtle conservation.

This neon blue river gets its color from a unique mix of bacteria and volcano minerals.

Sloth rehabilitation center in the jungle of Costa Rica.

These mysterious ancient stone spheres were created by a civilization lost to time and are now mostly lawn ornaments.