The last four extravagant street signs of London's historic banking street.

A mysterious pair of mice eating a piece of cheese is London's smallest public sculpture.

Exquisite wall sculptures carved in secret by an early quarryman in an obscure corner of the Paris Catacombs.

A Parisian exterminator's shop whose storefront displays stuffed rats hanging from traps.

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

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

High atop the Eiffel Tower is a small apartment built exclusively to entertain the science elite and make the rest of Paris jealous.

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

This may be the last of London's wooden pavements, which were once a common sight in the city.

Behind one of the world's most impenetrable vaults is a massive collection of retail silver.

A unique tribute to the millions of animals who served and died for the British military.

The sculpture of the deceased cockatoo flops atop its personal plinth.

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.

A charming 17th-century alley is lined with secondhand bookstores and antiquarian shops.

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

This ornate Victorian marketplace was the setting for Diagon Alley and the Leaky Cauldron in the Harry Potter films.

Known as the "Dodo Manège," this carousel features a herd of animals that have disappeared—or may be gone soon.

Indents in the pavement are all that remain from a grisly death machine in Paris.

19th century pendulum and a clock restored by a rogue group of guerilla artists.