A sinkhole and now a swimming hole, too, full of dazzling turquoise water.

This lost city belongs to one of the earliest civilizations in the world.

This crocodile-infested East Timor reservoir is also home to a spectacular half-sunken forest.

Ancient images hide within the park's caves.

A haunting place that is now home to thousands of birds.

A surprisingly large and sturdy ruin on the outskirts of a remote village.

These sacred totem houses connect the Fatakulu people with the spirits of their ancestors.

No one is quite sure of the origins of these idyllic natural hot springs at an abandoned mountain resort.

The tallest minaret in Yemen is 150 feet high and entirely made of mud.

This impressive system of tanks was used to store drinking water as long as 2,000 years ago.

One of Yemen’s oldest and most beautiful mosques was named for the incredible, historical queen buried inside it.

Elaborate patterns adorn the city's disappearing traditional architecture.

A mesmerizing reservoir nestled at the heart of a pre-Islamic Yemeni village.

A city built from mud and known as the "Manhattan of the desert."

The most alien-looking place on Earth.

The site of a bloody showdown between invading Iraqi forces and a cell of the popular resistance in Kuwait.

A private collection of over 30,000 ancient and modern items showcasing the beauty of Islamic calligraphy.

Wander among the ghostly ruins of an island where civilization flourished for thousands of years.

Lived-in building, bedecked with an astonishing array of mirror mosaics.

This isolated island is often capped by its own fluffy cloud.

This isolated structure beckons adventurers with sublime views of the Faroe Islands.

This remote island village was in danger of depopulating completely until a tunnel was built to connect it to the rest of the world .

The largest lake in the Faroe Islands seems to be held hundreds of feet above sea level thanks to an optical illusion.

This mysterious, medieval cathedral remains unbuilt but fiercely protected.