This cavernous swimming spot doubles as a home to the largest known colony of bats in Central Asia.

A fiery crater has been burning in the Karakum Desert since 1971.

This mysterious but iconic tapered tower appears in many Azeri fairytales and legends.

A unique museum dedicated to culture and artistry of carpet weaving.

The building's fluid, wavelike walls are a true feat of architectural ingenuity.

Home to nearly a third of the world's mud volcanoes, Azerbaijan is home to a messy, bubbling, and sometimes explosive landscape.

This dome-shaped mountain boasts amazing views and has a rich religious history.

The only quarter of the Old City not dedicated to a major world religion.

As the Dead Sea continues to deplete, massive sinkholes open along its banks.

The bluer than blue waters in these natural Israeli caves are reached via the world's steepest cable car.

Tel Aviv's popular neighborhood went though endless waves of transformation.

Legend says if you stick your thumb in the hole and it gets wet, your wish will be granted.

The largest hewn stone in history.

This no man's land slicing through the island is strewn with abandoned relics of another time.

An ornate plague column – built to celebrate life – claimed the lives of numerous artisans during its construction.

Tiny communists hammer away on the Olomouc Astronomical Clock.

This almost a century old piece of architecture had been overlooked by most, except for the drunk and the homeless

Crammed inside this grounded passenger plane is a bar that was once a Communist hang out and is now a ratty relic.

What looks like a suicide in progress is actually a statue of Sigmund Freud.

Macabre astrological automaton clock dating to the late 1400s.

A church of bones, decorated with 40,000 human skeletons.

Extremely famous in his native country, this Cracovian painter is all but unknown beyond Polish borders.

St. Mary's features one of the most spectacularly decorated cathedral interiors in all of Europe.

The former Nazi concentration camp stands as a museum to remember this dark chapter in European history.