After being lost for decades, this striking mural depicting the atomic bomb covers the wall of a busy Tokyo metro station.

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

Humble beginnings for one of the world's most famous scientists.

This cathedral hides a sculpted dog that determines your fate and an unexploded shell from World War II.

A colorful piece of contemporary art cheerfully clashes with Lyon's historical architecture.

The smallest museum in Basel, Switzerland, is a two-foot-by-two-foot window in the door of a 600-year-old house.

A nearly 25-foot concrete sculpture of Sylvette, Picasso's muse.

Rotterdammers' dirty minds gave this santa a dirty nickname and cursed it to a life of wandering.

Amsterdam's former hotspot for public executions and dissections.

This large copper bolt represents the benchmark for measuring sea levels in most of Europe.

One of Amsterdam's narrowest houses is located right across the canal from its widest.

The history and future of cannabis.

A beautifully eclectic mix of architectural styles.

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

A monument to Cuffy, a rebellious enslaved person who became a national hero in Guyana.

Georgetown’s most impressive building is also one of the tallest wooden churches in the world.

An 18th-century post box used to alert the church of sick and ailing foreign pilgrims.

A statue representing a lost Roman profession that was vandalized for centuries.

Romans decided this 16th-century "talking statue" was so ugly, they named it after a primate.

A detailed pachyderm supports Rome's smallest Egyptian obelisk.

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

One of several skulls claiming to belong to the beheaded St. John the Baptist is on display at this Roman church.

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

The skull of the patron saint of lovers lies in the Basilica di Santa Maria in Cosmedin—maybe.