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

The Vatican's secret porn-festooned bathroom was painted in erotic murals by one of the greatest artists of the Renaissance.

If you want to talk to the Pope you will have to stare down this surreal vision of Jesus rising from a nuclear hell.

Breathtaking and huge 430 year old maps of Italy.

Hidden beneath the famous St. Peter's Basilica is a veritable city of the dead that may hold the remains of St. Peter himself.

One of Belgium's oldest hospitals saw patients from the 13th to 20th centuries before becoming a museum.

The former home of a trailblazing surrealist is still filled with haunting dolls and grim paintings.

On rare days, this abandoned castle's gatekeepers open its doors, revealing the eye-popping splendor hidden inside.

This small church was constructed over the ruins of three temples dating to the Roman Republic.

The ruins of this medieval castle now stand as a monument against all wars.

A maze of crosses marks the jumbled divide between the Netherlands and Belgium.

The bronzed skull of a beheaded traitor was affixed to the city gate in the 17th century.

Rare wooden escalators lead deep down into an otherwise staggeringly monotonous tiled tunnel.

A monumental fountain in Rome features a large statue of Moses that has been criticized for centuries.

This Greek temple, open only an hour a day, was the site of a war of tastes between an architect and an artist.

A fantastical 13th-century fortification sandwiched by a modern hotel in central Brussels.

The remains of this 2nd-century Roman temple are incorporated into a modern building.

A magical and peaceful ruined Cistercian abbey in what is now southern Belgium.

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

Each spring, a dreamlike carpet of bluebells overtakes the forest floor.

A rare example of a medieval house in Rome adorned with a melancholic inscription.

What appears to be an ancient Roman temple is actually a Catholic church.

Legend has it that this bronze orb, which sat atop an ancient Egyptian obelisk, once held the ashes of Julius Caesar.

A popular legend claims that the famous pizza was invented at a restaurant in this alley.