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

Rome's semi-secret peephole vista is also a former Crusader stronghold.

Architectureal fantasy quarter of Rome.

The yawning maw of this pagan visage is said to bite off the hands of liars.

The final resting place of the poets Shelley and Keats.

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

This Roman arch marks the location of an ancient gate at one of the Seven Hills of Rome.

2300-year-old Roman road connecting the empire.

Jesus' footprints and the first catacombs in the world.

What might be the largest completely Jewish town in the world outside of Israel now faces dwindling numbers and empty streets.

A shrine of fire worship built on top of a natural flame.

Home to nearly a third of the world's mud volcanoes, Azerbaijan is home to a messy, bubbling, and sometimes explosive landscape.

Mysterious hillside with a continuously burning natural fire.

This steamship has been beautifully rusting off the coast of an Iranian island since the 1960s.

17th century mosque for Shah Abbas' harem.

This vast, water-filled underground labyrinth can only be toured by boat.

Ancient structures used to make and preserve ice in the deserts of Persia.

One of the world's largest salt caves is filled with fragile salt sculptures, salt rivers, and huge salt megadomes.

A 1,500-year-old, 3-story subterranean city where ancient Persians took refuge in times of war.

Hydraulic systems in an ancient underground Iranian city.

This beautiful system of tunnels built into natural rock serves as a centuries old plumbing system.

Iran's colorful terraces are a rare geological masterpiece.

Putrefaction plateaus in Iran, where the dead were sent for decontamination before going to their final resting place.

The palace of the King of Kings, burned by Alexander the Great.