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

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

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

Architectureal fantasy quarter of Rome.

The Pope’s secret escape route.

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

The mystic whose incorrupt corpse still attracts the faithful.

At the crypt of St. Mary of Eulogies and the Dead you are left alone to ponder mortality among piles of skulls.

A treasure trove of Renaissance-era funerary art in a Roman church built on top of Nero's grave.

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

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

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

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

Travel through the hidden underbelly of the city in colorful tunnels filled with art and history exhibits.

Geothermal waterfalls in Tuscany.

The hottest place on the planet.

Iceland's largest lagoon is home to stunning multi-colored icebergs.

The largest ice cave in the world is thought to be the entrance to hell according to Austrian legend.

Rising from the sea like a stone monster.

Explore the complex ecology of this multifaceted nature preserve by riverboat.

The Cathedral of St. Ambrose has been hiding a special parishioner within its walls.

The world's most active stratovolcano is almost always erupting.

A sulfuric hellscape in southern Italy.

Ample proof that watery ends make for well-preserved, millenia-old mummies.