This 1920s Dutch barge is now a floating bookstore.

This massive collection of British military artifacts includes the heartbreaking personal letters of the men in the trenches of WWI.

A cluttered and astounding collection of antiquities and curiosities.

A makeshift shrine to the late rock star is still kept up on the nondescript façade outside 1 Logan Place.

The anatomical-pathological collection of a man who changed surgery.

Hear the quietest sound from across the dome.

Wedged between two buildings at the Great Ormond Street Hospital is this secret music installation.

Eighty million natural history specimens call this gargantuan museum home.

Several plaster noses are hidden in plain sight around London's Soho neighborhood.

A vast overgrown cemetery, once known as one of London's "Magnificent Seven."

This London pub hides a peculiar secret: a recreation of the rooms shared at 221b Baker Street by Sherlock Holmes and Dr. Watson.

Banksy gives themself artistic license with this piece of London street art.

The perfectly preserved underground rooms where Churchill plotted the war against Germany.

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

This statue was given to France by the United States to commemorate the centennial of the French Revolution.

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

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

A favorite Paris bar for U.S. expats, including Gershwin, Hemingway, and James Bond.