Small on the outside, big on the inside, this church is an astonishing act of visual deception.

Two very green residential towers cleaning the air in one of Europe's most polluted cities.

The "Greatest Sewer" of ancient Rome is one of the oldest sewer systems in the world, and is still in use.

These medieval skyscrapers dominate the skyline of this small Tuscan town.

Medieval torture techniques with a modern conscience.

This Roman arch marks the location of an ancient gate at one of the Seven Hills of Rome.

A fairytale island floats in the middle of Italy's little-known Lake Orta.

The Pope’s secret escape route.

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

Five candy-colored villages on the Italian Riviera.

Jesus' footprints and the first catacombs in the world.

2300-year-old Roman road connecting the empire.

The only "Egyptian" pyramid in Europe and the legendary tomb of Remus.

The yawning maw of this pagan visage is said to bite off the hands of liars.

Hundreds of lucky felines haunt the ruins where Caesar was murdered.

This 1,300 year old monastery built atop a single rock was once only accessible depending on the whims of the tide.

This 1000 year old relic-filled cave monastery and UNESCO World Heritage Site also hosts an amazing micro-miniature museum.

When you've got to go, you've got to go.

The deepest metro station in the world.

One of the largest museums in Ukraine remembers the story of the German-Soviet War in iconic, brutalist style.

340-foot statue built to honour the Heroes of the Soviet Union.

A reconstructed medieval gateway that was the magnificent entrance to the capital city dating back to 1037.

When the Soviets destroyed the historic Armenian monastery they somehow left its bell tower intact.

Tower with a double-helix spiral, adorned with letters of the Georgian alphabet.