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

The remains of a town so thoroughly destroyed by French forces that the citizens simply left.

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

Three floors of musical instruments coming from all corners of the world and hundreds of years of musical history.

This Industrial Age architectural and engineering gem helps visitors and residents alike traverse Lisbon, “The City of Seven Hills.”

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

This sword isn't waiting for a king to pull it out. It was placed there by a saint.

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

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

This ritzy Italian market is built around a statue of an unforgiven heretic who was burned for his belief in an endless universe.

These "anatomical machines" are only one of the many strange items in this Italian crypt.

An ancient Egyptian temple in the middle of Madrid, Spain.

Jesus' footprints and the first catacombs in the world.

This quaint Italian town keeps losing ground as the sides of its plateau slowly erode.

Legacy of the earthquake that nearly wiped Lisbon off the face of the Earth.

In a city filled with Frank Gehry buildings, one stands out as one of the architect's weirder works.

The hallucinogenic center of the ancient world.

2300-year-old Roman road connecting the empire.

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

Renaissance villa and gardens complete with a tormented colossus.

Monasteries on rock pillars, once accessible only by frayed ropes.

Eighty million natural history specimens call this gargantuan museum home.

This community on a small Venetian island has taken to painting their houses in bright neon hues.