One of the earliest depictions of an Arthurian scene that is shrouded in mystery.

A special area of the National Archaeological Museum of Naples is located inside a metro station.

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

South of Bologna, a limestone grotto with a protruding waterfall and a floor full of cave pearls.

A room filled with frescos that make it seem like the walls are crumbling down while giants die in despair.

One of the oldest and most significant collections of Ancient Egyptian archeology outside of Egypt.

Psychoanalyst Carl Jung reported a paranormal experience after visiting this mosaic-lined Roman baptistry.

Why a column on the entrance is inscribed with a verse from the Quran is one of Sicily's many mysteries.

This building features dozens of faces along its facade, although one is a bit chilling.

This monumental fountain has moved around the city multiple times.

This medieval city gate is now a blend of the past and the modern world.

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

According to local folklore, this Roman sepulcher was once a throne for the Devil.

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

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

Macabre symbols of death and mummies on display set the tone of this Italian purgatory church.

This clifftop arch is a natural stunner.

A diverse collection of wax, bone, papier-maché and mummified relics.

Contains some of the world's more disturbing wax anatomical models.

An abandoned quarry hides an open-air gallery of huge sculptures, some made from the rubble of 9/11.

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

Before it was buried by volcanic ash, this fast-food restaurant fed the hungry hordes of ancient Rome.

This hidden alley near the location of Rome's first theater was the site of a curious miracle.

The Emperor Tiberius' palace of debauchery.