St. Francesca Romana, patron saint of drivers, resides in the church she founded.

A burial vault located under Tiber Island in the middle of the Italian capital.

This gallery commissioned by Cardinal Spada is known for its magnificent optical illusion.

The mystic whose incorrupt corpse still attracts the faithful.

This curious, round temple is the oldest still-standing marble building in Rome.

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

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

An Italian ghost town that fought obscurity, until a mysterious illness brought it to its knees.

This ancient market is often referred to as the oldest shopping mall in the world.

Museum dedicated to literary greats of the Romantic Period is also the home in which Keats met his untimely end.

Brass cobblestones mark the places where individual Holocaust victims were taken from their homes.

A mysterious chasm in the heart of the ancient Roman Forum, the Lacus Curtius was once believed to be a gateway to hell.

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

More sculpture than building, this architecturally significant temple was built on the spot of Saint Peter's crucifixion.

One of seven Jewish catacombs in Rome and one of only two open to the public.

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

A Nesting Doll of Churches.

The Pope’s secret escape route.

One of several skulls claiming to belong to the beheaded St. John the Baptist is on display at this Roman church.

This former Roman Catholic Church still contains the embalmed hearts and organs of 22 popes.

The martyr's wax-enhanced skeletal remains lie preserved in a glass case in the Santa Maria della Vittoria in Rome.

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

A fairy tale castle in modern Rome.

Jesus' footprints and the first catacombs in the world.