A Dutch passageway's artistic, aquatic-themed makeover pays tribute to the capital city's famed waterways.

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

A floating cat sanctuary on an Amsterdam canal.

This vast collection of smoking pipes from across the world spans centuries.

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

This unusual elevator doesn’t stop or slow down.

Cat art as far as the eye can see.

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

This lesser-known Frank Gehry building houses a treasure trove of cinema history.

Saintly bones pressed into a wax effigy of a Catholic superstar.

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

A Jenga-style cylindrical tower of books that appears to go on forever.

A steampunk-styled three-floor factory churning out art, activism, and electronic beats.

This doorless 20th-century elevator doesn't stop or slow down.

Apartment complexes built into huge repurposed natural gas tanks.

The housing complex served as an anti-fascist fortress during the Austrian Civil War.

Op-art architecture designed for happiness.

A mechanical clock built in 1914, with a rotation of 12 historical figures on its face.

A small museum filled with over 1,000 clocks, and one particular clock calibrated to run until the year 9999.

Dine amidst exotic plants at this former royal greenhouse.

An eerie, existential museum dedicated to the author of "The Metamorphosis."

A stately palace has been converted into the world's largest cannabis museum.

The spot where the fascist dictator made some of his most famous speeches including declaring war on Britain and France.

The curiosities and wonders of pharmacy in a delightful historic building.