The world's oldest bookshop still in operation.

These wire animal sculptures commemorate the exotic inhabitants that once called the Tower of London home.

An unusual ode to the late Irish playwright, complete with a squiggly bust and coffin-shaped bench.

More than a million titles fill the labyrinthine shelves of this prestigious private library.

The watery entrance for condemned prisoners heading to the Tower of London is still visible along the Thames.

Richard III supposedly disposed of his nephews' bodies here in an effort to seal his claim to the throne.

Six ravens are kept captive (but well-fed) at the Tower of London to prevent the fall of the Crown.

Catacombs turned marketplace.

The popularity of Sherlock Holmes led to the creation of his fictional address, turning the orderly London street numbers askew.

Kings Cross Station pays tribute to its role in Britain's best-selling book series.

Brussels' favorite peeing boy has a sister.

A little sculpture with a large wardrobe.

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

From Tintin to the Smurfs, Europe's greatest graphic icons are celebrated in a grand Art Noveau gallery.

Three floors of musical instruments coming from all corners of the world and hundreds of years of musical history.

This collection of over 50 murals celebrates Brussels' rich history as the self-proclaimed home of the "comic strip."

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

Vienna's diversity-themed traffic lights were inspired by the Eurovision Song Contest.

This series of Baroque passageways in Vienna's cultural center mix old architecture with modern art.

A neo-Gothic church built to thank God for saving the Emperor of Austria from an assassination.

Op-art architecture designed for happiness.

The final resting place for the remains of 143 Habsburg royalty.

The beautiful baroque library of the Hapsburg empire.

The celebrated eyesore created by starry-eyed sweethearts.