Architectureal fantasy quarter of Rome.

A forgotten "city of water" underneath the famous Trevi district.

An alchemist's "magic door" stands in the middle of a Roman park.

Rome is now home to a stunning food museum and library.

Its interior is adorned with some of the best examples of early Christian mosaics.

This gallery commissioned by Cardinal Spada is known for its magnificent optical illusion.

Medical history with an amazing, if frighting, collection of wax diseases on display.

One of the deepest indoor swimming pools in the world.

A wonderfully kitsch bookstore the size of a supermarket.

Only museum in the world devoted to bookbinding and book arts holds a permanent collection representing five centuries.

Lavish royal estate punctuated with heated greenhouses.

Meet the bronze beloved pet to a family of famous peeing statues.

This modern arts center is built around a gem of late-Baroque architecture.

Theme park featuring miniature replicas of European monuments.

Climb inside an iron crystal magnified 165 billion times its normal size.

Rome's semi-secret peephole vista is also a former Crusader stronghold.

This museum is filled with an eclectic collection of unique inventions.

Preserving the research tools, unexpected inventions, and odd collections of generations of college professors.

A UFO-shaped event building originally intended to be a science museum showcasing the future.

Crouch down, stretch tall, and be sure to flail your legs to pay homage to the Monty Python classic.

Inspired by "The Starry Night" this Dutch bike path turns into a glowing work of art each night.

Nestled in the woods lies this land art project: a hybrid between park, maze and natural monument.

Organisms normally seen under a microscope decorate this church.

Take a stroll through the hellish grotesques of Hieronymus Bosch in this elaborate Netherlands church.