Claude Monet was baptized in this lavishly ornate Paris church.

The industrial architecture honors the laborers who brought the Exposition Universelle of 1900 to life.

Natural history museum celebrating biodiversity with a parade of taxidermy animals.

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

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

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

Site of a classic 19th-century physics experiment to prove the earth is rotating.

France's most famous cemetery, with some of its most curious tombs.

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

The graveyard with the highest IQ in Britain.

It celebrates a very stinky task and salutes London's fatberg-vanquishing team.

This bewitching Babylonian goddess haunts a hallway of the British Museum.

This unassuming alcove in London’s famous Tower Bridge once served to capture, store, and display dead bodies from the River Thames.

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

An architectural oddity hides in plain sight on this iconic London bridge.

Tucked away in the Tower of London is the weapon once used to execute high-profile prisoners.

The ritual has been performed uninterrupted for nearly 700 years.

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

The first geometric self-supporting spiral stairs in Britain are a truly beautiful sight.

These official units of measurement—including chains and perches—lie hidden beneath tourists' feet in a popular London hub.

Where condemned pirates met their grisly end at the gallows on the River Thames.

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

London's smallest police station is barely the size of a phone booth.

After nearly 60 years, there's still a bear at Paddington Station looking for help.