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

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

The mystic whose incorrupt corpse still attracts the faithful.

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

A huge enchanting public park just outside the ancient walls of Rome.

This hill made entirely of ancient Roman jars was simply a garbage dump to the people of the time.

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

2300-year-old Roman road connecting the empire.

Jesus' footprints and the first catacombs in the world.

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

This open air archeological site houses almost as much wildlife as it does classical religious artifacts.

A striking symbol of the Bulgarian capital.

Sofia's legislative center is continuously reinventing itself.

A vast Communist-era exhibition space in the Bulgarian capital.

Byzantine emperors ruled, lived, and died in this 13th-century palace-turned-museum.

A section of the long chain that blocked enemy ships from entering Constantinople.

1513 Turkish world map, full of European state secrets and snarky commentary.

A marvel of Byzantine engineering under the streets of Istanbul.

Legend says if you stick your thumb in the hole and it gets wet, your wish will be granted.

Five sultans and their families rest in eternal splendor, teeming with overlooked beauty and drama.

This remarkably well-preserved Egyptian plinth is pretty well traveled for a giant piece of stone.

Ancient serpentine sacrifice holder that has stood the test of time.

A sixth-century Byzantine cistern hidden below a modern carpet store.

The only Roman honorific column in Istanbul.