Scattered throughout London are ancient remnants of the city's former bounding wall.

The curios of pharmacist and collector Henry Wellcome.

A little slice of Japan and its aesthetics in London's Holland Park.

Catacombs turned marketplace.

One part local history, 99 parts gruesome haunted house.

This 1920s Dutch barge is now a floating bookstore.

This South London cemetery holds the remains of more than 15,000 people.

Eighty million natural history specimens call this gargantuan museum home.

This skewed English house has looked like it's going to fall over for centuries.

Paris' linguistic guide to the international language of, yes, love.

This charming cobbled backstreet is the most Instagramable street in Paris, much to the residents' annoyance.

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

Chicago's Navy Pier on Lake Michigan was a training hub for aircraft carrier pilots during WWII.

A journey begins with a single step, and for many, the road-trip of a lifetime started at this Chicago intersection.

The twin towers in this Chicago fountain use 50 foot tall video screens to spit on people.

This massive stained-glass masterpiece is thought to be the largest Tiffany dome in existence.

This crumbling 14th century chapel became so unstable the roofing apparently collapsed during a wedding ceremony, narrowly missing the curate's head.

Amsterdam's former hotspot for public executions and dissections.

One of Amsterdam's narrowest houses is located right across the canal from its widest.

Established in 1638 to battle the Black Death, this botanical garden is a treasure trove of rare flora.

Museum preserving torture methods from the past.

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

The eternal resting place of the last highwayman hanged in England.

The oldest public library in Ireland.