A collection of short standing stones covers this hillside.

An abandoned village where the ruined foundations cling to a cliff.

This rare surviving broch is one of Scotland's most impressive Bronze Age structures.

A castle in the Scottish Highlands has been continuously inhabited since the 1300s.

Where the sleeping monsters of Scotland's oil industry are left to rust.

A pagan tradition of draping trees with rags eerily lives on.

A centuries-old complex of hand-dug stone chambers has sheltered locals in times of trouble.

A sublime medieval path adorns the marble floor of one of the most beautiful Gothic cathedrals in France.

The encased skull that is widely believed to belong to St. John the Baptist.

Science fiction's grandfather has a fittingly marvelous tomb.

Ancient paintings known as the "Sistine Chapel of Cave Art."

Ever hear of the Milazzo Cage?

Its interior is adorned with some of the best examples of early Christian mosaics.

Also known as the Square Colosseum, this building is a prime example of fascist-era rationalist architecture.

Remnants of a 4th-century church with vivid medieval frescoes and ancient sarcophagi hide beneath this old basilica.

This subterranean shrine beneath a bike rental store celebrates the iconic Italian scooter.

One of Catholicism's four major basilicas has a series of papal portraits that are said to predict the end of the world.

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

The studio built by fascists in the hopes of "reviving the film industry" with the occasional propaganda film opportunity thrown in.

Installed in an act of one-upsmanship, the annual sundial in this church is also a symbolic victory for the Gregorian calendar.

This beautiful park on the outskirts of Rome protects the ruins of two colossal ancient aqueducts.

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

Architectural monsters are devouring this palace's every door and window.

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