This geometric feat is a testament to the Incas' mesmerizing architectural abilities.

Situated on a sacred Inca site, this 16th-century cathedral took nearly 100 years to build.

Built on the remains of one the Incas’ most important gathering spots, this square keeps the spirit of a fallen empire alive.

It took 82 years and four different plaques to finally get the story right.

The intricate stonework of Machu Picchu serves as a testament to Incan engineers.

The site where the summer solstice helped ancient Greeks sync the lunar and solar calendars.

Rest stops along this pathway offer some of the best views of the Acropolis of Athens.

A Byzantine-era church hidden in a wooded area below the Acropolis.

These caves secretly held national treasures during World War II.

The ruins of the largest gladiatorial school in Rome are largely hidden under modern streets.

Architectureal fantasy quarter of Rome.

This hydrochronometer was invented by a Dominican monk and is a prime feature in this garden.

2300-year-old Roman road connecting the empire.

The Pope’s secret escape route.

This is the oldest Roman-made bridge in the city still existing in its original state.

Historic fortifications form the boundary of Vatican City, but it’s not entirely surrounded by walls.

This ritzy Italian market is built around a statue of an unforgiven heretic who was burned for his belief in an endless universe.

This tiny chapel withstood a massive mudslide and flash flood.

Five candy-colored villages on the Italian Riviera.

A lover's walk between hilltop towns, decorated with graffiti love notes.

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.

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

In the past, Renaissance sex workers were encouraged to entice customers on this bridge.