A scientific repository of goiters, boils and other ailments throughout Mexican history.

Clap your hands at the base of the pyramid, and the song of a sacred Mayan bird will echo through the air.

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

These haunting ruins of a 700-year-old Prehispanic city have witnessed centuries of wars and massacres.

No telescopes, no power, no gift shop: The Observatory of Chichen Itza, one of the world's oldest observatories, takes astronomy back to basics.

Every equinox this Maya pyramid puts on a spooky ancient light show.

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

A tiny church on a man-made island in the Adriatic.

These historic defenses ensured the city within would survive hundreds of years of occupations, sieges, and invasions.

An intimate look into the apartments of Jounieh via cable car.

The oldest museum in Borneo is a cornucopia of rare taxidermy and human skulls.

Malaysia's floating mosque.

Holy Hindu shrine in an enormous, monkey-filled limestone cavern.

1800 rooms of single-family residence in Brunei.

Lonely minaret stump of a destroyed city.

Built entirely of interlocking pieces, construction of this Chinese Muslim house of worship required zero nails.

Extremely isolated Silk Road caravanserai in the middle of nowhere.

Kuwait City's uniquely designed water towers look straight out of a retro sci-fi cityscape.

In Kazakhstan, a colorful cathedral with many lives once survived the most powerful earthquake in the region.

Nicknamed Kazakhstan's Grand Canyon, this natural wonder lies east of Almaty near the Chinese border.

The lovely lake that was naturally dammed, then naturally destroyed, then unnaturally saved.

A brilliant turquoise lake in the mountains.

An oasis of shade and color amidst the bustle of the old city.

A more chill but no less fascinating version of the famous ancient archeological site.