Established in 1638 to battle the Black Death, Hortus Botanicus Amsterdam is a treasure trove of rare flora.

This unattributed sculpture in Amsterdam is hiding in plain sight.

An ancient passage filled with stalls selling used books, once frequented by Vincent Van Gogh.

Museum preserving torture methods from the past.

An Amsterdam street lined with antique shops each one dedicated to a different obscure collection.

The world's only museum devoted to the wonders of fluorescence.

The world's largest private telescope collection hides in a secret wing of a Dutch auto museum.

Lumps of significant stone from around the world surround a flaming monument for peace.

In the Netherlands, one of the world's largest private car collections can be found.

A seven-century-old jail tells a not-so-pleasant history of crime and punishment.

An abandoned underground bathroom is now a space for public art.

A special shop catering to the needs of things that go bump in the night, and also helps kids become writers.

A collection of comics, graphic novels, animation and caricatures devoted to exploring this often overlooked art form.

A toy store with a century-long history preserves the craftsmanship of playthings of the past.

This 1920s Dutch barge is now a floating bookstore.

A mysterious artist-run cabinet of curiosities and library.

A 2000-year-old Roman amphitheater lies just below Guildhall Yard.

A cluttered and astounding collection of antiquities and curiosities.

The largest of London's subterranean rivers and once a mad, bad center of London life.

London's smallest police station is barely the size of a phone booth.

This wildly-tiled artist's palace is a living and growing account of the creator's life, loves, and labors.

The world's first underground farm is in a World War II bomb shelter beneath the streets of London.

The site of London's first coffee house has been serving refreshments of one kind or another for 360 years.

A makeshift shrine to the late rock star is still kept up on the nondescript façade outside 1 Logan Place.