Former hunting lodge of a duke who was an avid collector of impressionist works.

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

19th century pendulum and a clock restored by a rogue group of guerilla artists.

The very center of Paris is surrounded by a bevy of strange good luck rituals.

This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

Elevated freight railway turned wildly successful urban park.

An unusual round church in London with a Templar past.

The popularity of Sherlock Holmes led to the creation of his fictional address, turning the orderly London street numbers askew.

This massive stained-glass masterpiece is thought to be the largest Tiffany dome in existence.

A monument to the art of slicing people open.

This morbid, delightful curiosity shop offers everything from animal bones to human teeth.

Four glass boxes hover over 1,000 feet in the air to give visitors an unparalleled view of Chicago.

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

Mrs. Mallard and her brood are a beloved fixture in Boston Public Garden.

The site of the famous Nazi book burning campaign of 1933 remembers its "Night of Shame".

On the Spree bank, discover one of the last reminders of a symbolic wall that divided, and was torn down by the people.

A museum dedicated to a Cold War era sausage.

Thousands of coffin-like pillars make up this controversial Holocaust memorial.

This former Baroque palace on the historic Calle Montcada is a rare architectural gem and was once the meeting place of an aristocratic scholarly society.

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

One of Antoni Gaudí's most classic buildings is well-known for its "dragon-back" design.

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

Home to over 200,000 artifacts, this museum attempts to guide visitors through the ancient history of Beijing and Imperial China.