A 2,000-year-old computer demonstrates remarkable engineering and astronomical precision.

This ancient Greek place of assembly and marketplace is being revealed layer by layer below the modern Athens cityscape.

Ancient mysterious ruts carved in the bedrock.

Burial grounds for more than 1,000 bodies deep under the modern town of Rabat.

An abandoned set from the 1980 film "Popeye," claimed and repurposed as a theme park by creative locals.

An expansive complex of subterranean tunnels is all that remains of one of Europe's most formidable medieval fortresses.

This noble mash-up in eastern Luxembourg is part Medieval, part Renaissance, all castle.

Budapest's Communist-era statues, banished to the suburbs.

Twisted girders are all that remain of an Icelandic bridge that was wiped out by a combination of volcanic heat and glacial floods.

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.

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

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

Three columns of volcanic rock shoot out of the ocean.

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

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

This fantastical waterfall is hidden in a cave located in a cracked cliff.

The unique waterfall in Iceland's south features a backdrop of geometric black lava columns.

Medicinal spa created from the mineral-rich runoff of a geothermal power plant

A thriving artist's wonderland located just 6 kilometers from Korea's DMZ.

Secret North Korean passage discovered below the world's most dangerous border.

After a profound show of devotion for his master, a dog becomes the symbol of loyalty for an entire nation.

Legendary site where an evil bishop was devoured by rodents.

A memorial for a young woman and her ghost, which are claimed to have caused countless deathly shipwrecks.