A building so large that it has its own weather.

A open air theatre built on a cliff by an eccentric British woman.

A marvel of Byzantine engineering under the streets of Istanbul.

A beautiful 62-acre Catholic shrine and botanical garden.

A modern day curiosity cabinet.

Pilgrimage site for star-crossed lovers.

A minotaur, a labyrinth, and a dubious restoration pull in visitors from around the world.

A tribute to Ponce de Leon's supposed quest for eternal youth.

Strange red rock formations that have been attributed to a higher power for hundreds of years.

A peculiar mansion built by the troubled heir to the Winchester Rifle Company fortune.

A "gravitational anomaly" located in the redwood forests just outside of Santa Cruz, California.

Founded as a refugee camp, now a popular tourist spot.

These azure waters were thought to lead to the Mayan Underworld.

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

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

Hundreds of prehistoric stones, arranged in perfect lines in a French field.

Famously misunderstood wonder of the ancient world

Fascinating town where normal life interfaces with the occult.

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

The secular incarnation of a religious meditation.

The hallucinogenic center of the ancient world.

Roman ruins top white travertine terraces formed by ancient hot springs.

In this historic region, homes and churches are carved into ancient volcanic rock formations.

Roman ruins, natural methane fires and a lovely beach.