Amsterdam's narrowest house facade is a monument to 17th-century tax evasion.

The history and future of cannabis.

The attic of a four-century-old canal house hides a clandestine church.

This 22-floor tower's Skydeck offers panoramic views of Amsterdam.

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

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

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

Speak to a companion on the other side of the room loud and clear through this architectural anomaly.

What was meant to be a temporary exhibit is now a permanent fixture at the St. Louis Zoo filled with beautiful birds.

A floating museum that was sunk by a flood and left to rot in the tides.

Eighty million natural history specimens call this gargantuan museum home.

The monster at the center of the Darwin Center Spirit Collection.

After nearly 60 years, there's still a bear at Paddington Station looking for help.

A charming 17th-century alley is lined with secondhand bookstores and antiquarian shops.

An easily overlooked stretch of ornate window fronts and gaslight lamps that could be right from the pages of Dickens.

The John Snow Memorial marks the epicenter of London's 1854 cholera epidemic.

Neon artworks light up this dark Edinburgh tunnel.

Overlooking the burial ground is a tower designed to prevent thieves from snatching the recently deceased.

A verdant 17th-century-style garden hidden along Edinburgh’s Royal Mile.

This Scottish graveyard is the final resting place of the man who inspired the character Ebenezer Scrooge.

This alley off Edinburgh's Royal Mile contains remnants of the city's seedier history.

This 16th-century close preserves an unusual piece of Edinburgh's transportation history.

A labyrinthine network of chambers with a storied past hides below Edinburgh's South Bridge.

A book bound in the skin of an infamous criminal, along with countless other specimens.