Little island known for its massive beachfront "flowerpot" pillars.

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

This legendary city has been a tourist attraction for centuries.

One of England's most famous churches hides a pair of little known architectural treasures.

Balconies that have a most unusual accent.

What if all public housing projects had been designed by "the Pygmalion of modern architecture," not only their prototype?

A shrine honoring a legendary ghost bride lies within this vibrant temple.

Hoax, mistake, or evidence of dinosaurs in human times?

A battle between nature and architecture in the Cambodian jungle.

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

A hidden treasure of an abandoned city lies deep in the jungles of Campeche, Mexico.

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 abandoned building that once tightened a power line that stretched across Messina Strait.

This bustling Italian plaza is built on the ruins of an ancient Roman amphitheater.

The only visible reminders of an elaborate engineering project that kept the tower from reaching the tipping point.

In Florence's great Duomo, a 26 foot fresco honors a mercenary famous for attacking Florence.

The secret medieval communication system will whisk your words above the noise of the crowd.

Two stone columns flank the grand Venice square, but there were supposed to be three.

The 1,000-year-old abbey is the birthplace of modern musical notation.

A dead saint, a deadly poison, and a mysterious holy ooze.

The only museum with its curator—and her pets—buried inside.

An extensive collection of reliquaries containing the bones of saints housed in the largest Catholic church in Venice.

A petite white lighthouse perched on the ancient core of Stromboli Volcano.