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

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

The engineering wonder and pleasure dome of a much-maligned emperor still holds undiscovered secrets.

The skull of the patron saint of lovers lies in the Basilica di Santa Maria in Cosmedin—maybe.

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

This hidden Art Nouveau courtyard is an opulent feast for the eyes.

The only remaining arch of the oldest stone bridge in Rome stands in the middle of the Tiber.

A forgotten "city of water" underneath the famous Trevi district.

Harlequin costumes, signed scripts, and armor-wearing puppets.

Ever hear of the Milazzo Cage?

A memorial to Brazil's little-known role in World War II.

The remains of 50,000 World War I soldiers rest under a towering arch overlooking the Alpine battlefields.

A small cell adjacent to this church was once the bedroom for a renowned saint.

A 17th-century doorway in a small Sabine village is a portal into the mysteries of alchemy.

This small but lovely sinkhole lake is the last remnant of a great prehistoric water basin.

Claude Monet immortalized this medieval bridge in two of his paintings.

Legend said this huge, gnarled tree sheltered the saint during a storm.

The oldest scientifically dated tree in Europe lives on a remote cliff.

The old church, buried by the 1784 Mount Vesuvius eruption, is a remarkably well-preserved place where people now pray for the souls of the dead.

The second-highest village in Lazio has attracted artists for 400 years and is now a spectacular open-air art gallery.

A fortified medieval basilica on the Caelian Hill preserves extraordinary frescoes and one of Rome's most beautiful hidden cloisters.

A medieval stronghold rising over the ruins of ancient Roman villas along Rome's southern coast.

Contrary to what its name suggests, you won't find any bunnies here.

An unusual "skull with ears" sits in the crypt of this small church tucked away at the end of a narrow alley.