This memorial commemorating fallen Swiss Guards of the French Revolution has been called the saddest stone in the world.

A nearly 500-year-old sculpture depicts a man eating a sack of babies, and no one is sure why.

This fort dates back to 1588 and was colonized by the Portuguese, Dutch, and English and sits prominently on the Indian Ocean where azure water lap the coast.

This ancient cave temple complex is the largest and best-preserved temple complex in Sri Lanka.

This elaborate temple was built around one of the Buddha's teeth.

An ancient stone fortress considered by many to be the eighth wonder of the world.

Huge herds of Asian elephants can be seen walking, bathing, and just chilling at this Sri Lankan park.

One of the earliest depictions of an Arthurian scene that is shrouded in mystery.

A medieval, mosaic-lined baptistry built by a heretical Christian sect.

Psychoanalyst Carl Jung reported a paranormal experience after visiting this mosaic-lined Roman baptistry.

This building features dozens of faces along its facade, although one is a bit chilling.

This medieval city gate is now a blend of the past and the modern world.

An incredible mosaic-lined monument said to have held the remains of an ancient Roman empress.

A spitting ode to a German serial killer.

The intricate geometry inside this Baroque-style dome was designed to create "terror of the human soul."

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

This futuristic German television spire is actually the world's largest digital clock.

Before it was buried by volcanic ash, this fast-food restaurant fed the hungry hordes of ancient Rome.

A local student's chance encounter with Keith Haring led to the creation of one of Europe's largest murals.

This cathedral hides a sculpted dog that determines your fate and an unexploded shell from World War II.

Stare out over the lagoon and beyond from this 10th-century campanile on the island where the city of Venice began.

Böttcherstraße's bells, extolling Nordic virtues and the great conquerors of the world.

Legend has it this fountain built to symbolize the Pope’s power hides a strange secret concerning Neptune's manliness.

Memorials at a Florence railway station remember the citizens who were deported from Italy and sent to extermination camps.