These pillars at the main entrance of this church are actually a hidden musical instrument.

The oldest-known example of a historic architectural style recognized by UNESCO.

The ruins of this monumental city founded by the first Roman Emperor are strangely overlooked by most travelers.

This legendary city has been a tourist attraction for centuries.

Built by the Ancient Greeks, this chariot bridge is still in use today.

Overlooked archeological site close to the city of Patras.

The first public library in the Americas has more than 45,000 books dating back to the 15th century.

The splendor of this 17th century golden chapel has led it to be called the "eighth wonder of the world."

This foreboding building was the headquarters of the terrifying Spanish Inquisition in Mexico.

This stunning and ethereal mural symbolizes the beauty, unity, and diversity of humankind.

The unique collection often goes unnoticed by visitors focused only on the archaeological objects.

It's believed this golden brick is part of the legendary lost Aztec treasure.

Abandoned figurines adorn a small plot on the side of a craft market's entrance.

In Coyoacán, a pair of coyotes crown a public fountain in reference to the ancient Aztec name of the borough.

Frida Kahlo's childhood home, now a museum of her life and works.

A museum in the former home of Marxist revolutionary Leon Trotsky.

Europe's "only museum dedicated to the decapod" is full of quirky and absurdist displays, including one featuring the "famous" Giant Crab of Margate.

A sunken idol welcomes parishioners to Davy Jones' Locker.

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

Massive galleon from a box-office bomb docked in Genoa.

Although called a funicular by both its owner and the locals this historic railroad is actually a rack and pinion system.

Once home to one of the oldest banks in the world, this building is also where Marco Polo's famous travelogue was written.

A century-old tower with great harbor views in a quiet space, hidden among skyscrapers.

Teeming with illegal goods and services, this towering maze of vice is also a popular tourist accommodation.