Breathtaking and huge 430 year old maps of Italy.

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

The Pope’s secret escape route.

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

Inside this building is another country within Rome, a sovereign entity without a physical territory.

Ancient ruins hidden underneath a modern luxury hotel.

St. Francesca Romana, patron saint of drivers, resides in the church she founded.

An ancient Roman temple first dedicated to an emperor's wife is now a church.

A mysterious chasm in the heart of the ancient Roman Forum, the Lacus Curtius was once believed to be a gateway to hell.

This ancient Roman prison is decorated with an upside-down cross not as blasphemy but as saintly tribute.

The best preserved Paleochristian basilica in Rome hides a number of oddities and secrets.

Nordic giants resurrected from the sea and restored to their former greatness.

The original home of the Lego has a huge amusement park dedicated to the iconic plastic toy.

Nearly 40 miles and 1,000 years of limestone mines under Denmark.

This bellfry was once said to be the Devil’s lair—or perhaps the home of a mischievous gnome?

Tiring of digging out the door to this church for every service, it was eventually abandoned to the sands.

The northernmost point in Denmark is a turbulent sandbar created by two clashing seas.

An abandoned lighthouse awaits its destiny: being buried under shifting sand.

The highest point in Denmark has been a matter of dispute for over 80 years.

Mounds, rune stones, and a 1,000-year-old church, left behind by Denmark's first two kings.

This vestige of Seychelles’s colonial past now resides in a busy intersection and didn’t chime for its first 96 years.

A British general, a suggestive tree, a map of paradise.

This hanging crocodile is thought to be the "dragon" that once plagued a Czech city.

A peculiar clock commemorates a historic victory won by ringing the noonday bell an hour early.