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

This large copper bolt represents the benchmark for measuring sea levels in most of Europe.

Where royalty waits in the height of luxury.

Europe's first floating restaurant is home to a hilarious legend.

This unusual elevator doesn’t stop or slow down.

Amsterdam's former hotspot for public executions and dissections.

Amsterdam's Red Light District leaves little to the imagination.

One of Amsterdam's narrowest houses is located right across the canal from its widest.

The former headquarters of history's oldest megacorporation.

The facade of this bank has changed little over the centuries, including its unique welcome sign.

In the days before house numbers, these colorful signs held clues about various buildings' purposes.

A unique work of automotive art calls this shopping center home.

A hidden church in a hidden courtyard tells the story of the Miracle of Amsterdam.

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

A horde of stray cats rule in this secluded Parisian cemetery under a bridge.

A scandalous Art Nouveau collaboration that set Paris all atwitter at the turn of the century.

Twelve grave-faced marble angels guard the emperor's tomb at Les Invalides.

A modern-day Lascaux cave underneath Paris.

This former “ante-chamber to the guillotine” has been refurbished to illustrate the brutal history of French justice.

The ruins of a Duke's bucolic dream, where camels once roamed alongside "Dutch" windmills and faux-Italian vineyards.

A museum of carnival attractions where you are invited to ride the rides.

Notorious artist squat renovated into legal studios.

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

This massive library holds what was once the largest book collection in the world.