A Nesting Doll of Churches.

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

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.

A fairy tale castle in modern Rome.

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

2300-year-old Roman road connecting the empire.

Rome’s legendary peephole vista is also a former Crusader stronghold.

A master of trompe-l'oeil creates a stunning, tourist-fooling dome out of a flat ceiling.

An alchemist's “magic door” stands in the middle of a Roman park.

1,300 chamber pots and their eccentric collector.

Hamburg's first legal sex work is relegated to a gated street that still does not allow pedestrian women.

This dockworkers' lunch joint has been left leaning by a century of storm floods.

Hamburgers are intensely proud of their tunnel beneath the river.

Once the tallest building in the world, this abandoned church is now a monument to the destruction of WWII.

An 18th century fountain and two columns are all that remains of Rome's forgotten river harbor.

Inside this McDonald's you can dine on your Big Mac and fries next to a 2,500-year-old Roman wall.

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

The final resting place of the poets Shelley and Keats.

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

In the fictional world of Kcymaerxthaere, celestial wonders marked a portal to a powerful route of travel at this site in Madrid, Spain.

This small church was constructed over the ruins of three temples dating to the Roman Republic.

Plaques on its facade commemorate the Tiber's most destructive deluges.

A deep mark on the remains of a Roman temple, believed to be left by a legendary warrior.