The world's largest piece of copyrighted artwork.

A former waterfront market is now in the center of town due to some interesting Boston engineering.

Ice cream stand, snack bar, and time capsule of milk conveyance.

Possibly the world's largest hourglass only needs to be reset every New Year's Eve.

This Hungarian castle was built out of cardboard and wood until it proved so popular that it got upgraded to stone.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

Debatably clever, or just plain honest hotel advertised as "The Worst Hotel in the World."

A beautifully eclectic mix of architectural styles.

This historic address is home to the beloved ball and is an almost totally empty building among the most expensive real estate in the world.

This sculpture by artist Fritz Keonig survived the 9/11 attacks and now stands as a monument to the victims.

Whisper secrets in a busy station only to be heard on the other side of this acoustic arch.

This automated sculpture of two men peeing will spell out text messages with their micturition.

Despite attempts by local police to discourage it, Beatles-inspired graffiti has been a means for artists to air grievances for decades.

Macabre astrological automaton clock dating to the late 1400s.

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

2300-year-old Roman road connecting the empire.

Rome's semi-secret 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.

Hundreds of lucky felines haunt the ruins where Caesar was murdered.

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."