One of the world's tallest flagpoles.

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

Malaysian fireflies create a dazzling display as thousands light up in unison.

Built by the Portuguese colonists in the early 16th century, this fort is one of the oldest European structure in Asia.

A "miracle" that seems to produce more holy fistfights than holy revelations.

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

The oldest known university in the world is in Fez, Morocco.

Traditional 11th-century outdoor tannery.

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

Naturally preserved bodies are eerily staged throughout the crypt in varying poses.

A copy of the famous statue can be found in this Florence piazza, along with one of the most breathtaking views of the city below.

A sulfuric hellscape in southern Italy.

A star-shaped fortress town fort built in the geometric model of the Renaissance utopian city.

"Stairs of the Turks", a chalky white cliff eroded conveniently into stairs, allowing for easy pillaging.

The walls and streets of the ancient city are peppered with penises.

This strange bovine gargoyle is said to have been put in as a passive aggressive form of revenge.

Italian cave with exceptional acoustics and an unsavory history.

Erotic art covers the walls of the largest ancient pleasure palace.

Ancient snack bar of the Roman Empire re-opened.

The world's most active stratovolcano is almost always erupting.

Romans built the world's tallest artificial waterfall in 271 BC.

Every day is like Christmas on this street where the traditional Neapolitan nativity scene comes to life.

Legend says this mysterious stone head belongs to a woman who was petrified by an alchemist.

This private skyway is filled with art and was expanded explicitly so that Hitler could appreciate a river.