This modest marker near Notre Dame identifies the very center of Paris.

400-year-old garden, restored to beauty.

This antique prison is a tourist attraction with a sordid past.

An ancient hotspot for spotting schools of fish.

A pair of club-wielding guardians stand watch over London's first public clock to feature a minute hand.

The (fictional) address of Sweeney Todd's bloody barbershop.

One of the few remaining examples of 19th-century London’s attempt to clean up its reputation.

An ancient healing font dedicated to an 11th-century matriarch was moved to make way for progress.

This extinct volcano rises above Edinburgh and is special for its panoramic views over the city.

Portlandia is the second-largest copper repoussé statue in the United States.

This castle-like building in Manhattan helped destigmatize cancer in the 19th century.

The middle finger of modernity.

The famous sculptor left his mark on this Italian wall in an internationally protected example of street art.

What remains of the summer palace of King Kamehameha III.

This museum of Hawaiian and Polynesian culture is the legacy of the last descendant of the Kamehameha Dynasty.

One kilometer of thick brass rod laid out before your eyes.

A room in New York City that contains 250 cubic yards of dirt.

Hidden in Central Park's Ramble is a troublesome cave buried just beneath the surface.

This Puget Sound military post has a long, turbulent history as a gateway to the Pacific.

An effigy of Vancouver's Gastown neighorhood's namesake.

The colorful, smiling concrete silos of Vancouver.

A working steam clock, one of only a few in the world, located in Vancouver's Victorian Gastown.

A walk through the historic city center, under the streets of Seattle.

A giant Troll lurks under one of Seattle's oldest bridges.