This lower Manhattan bar is set up in an old bank vault that rests beneath a skyscraper that hides even more historic splendor.

The world’s oldest and biggest bookstore stocking only mystery, crime fiction, espionage, and thrillers.

A celebration of capitalism in Midtown.

A playground inspired by differential calculus dangles from the ceiling of the Liberty Science Center.

One of the last umbrella repair shops in Paris upholds the nostalgic art of umbrella making.

The oldest stone house in Paris was built by its most famous alchemist.

Dolls of all shapes and sizes display the eras of femininity in this spooky and beautiful collection.

Indents in the pavement are all that remain from a grisly death machine in Paris.

A museum dedicated to one of Paris’s most famous residents, tucked into a corner of one of the city’s most famous squares.

Barcelona's historic 19th-century sewers, whose foundations were laid in medieval times, are open to the public for exploring.

This semi-secret storybook hedge maze is also the oldest garden in the city.

Barcelona's only remaining tram system takes riders to the Tibidabo funicular.

Bask in the 19th century grandeur of an eccentric Freemason millionaire's private gardens.

The abandoned ruins of a beautiful medieval castle just outside Barcelona.

A science fiction-inspired apartment building designed by a famous Spanish architect.

This picturesque mansion has gone from opulent ruin to nature museum.

Cathedral carved out of salt, located a mile below the earth's surface.

Former drug lord’s manor, now a theme park. Watch out for the hippos.

The (usually) serene burial place of the world's most notorious drug lord.

Ripped apart by a bomb in 1993, the shell of Pablo Escobar's infamous vacation house still stands.

This city park wants you to take your shoes off.

This unofficial museum details the rise and fall of Colombia's most notorious narcotrafficker, Pablo Escobar.

A museum of memories in what was once one of the most violent cities in the world.

The remains of an ancient settlement in one of the oldest archeological sites in South America.