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

An alleyway plaque is all that remains of the independent Texas' envoy that forgot to pay their rent for over a century.

Hear the quietest sound from across the dome.

One part local history, 99 parts gruesome haunted house.

A hands-off space for graffiti artists to hone and display their skills.

A kaleidoscopic warehouse-maze of handmade neon signs.

One of the few remaining casualties of the London Blitz, this destroyed church has become an enchanting public garden.

Touching this 18th-century Scottish philosopher’s toe allegedly conjures good fortune.

New York's southernmost subway station is whimsically wavy.

A monument to the thrice mayor of London who according to lore made his fortune by selling his rat-chasing cat.

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

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

A student driver's nightmare.

A huge musical instrument played by the ocean.

Two plaques commemorate the site of Shakespeare's first theatre.

The rose garden in Regent's Park where Pongo and Perdita met for the first time in Disney's "101 Dalmatians."

A roadside shrine to a late rock god only remains thanks to the unyielding efforts of his fans.

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

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

This doorless 20th-century elevator doesn't stop or slow down.

Countless grotesque faces stare out from this eerie Prague art wall.

A Jenga-style cylindrical tower of books that appears to go on forever.

Macabre astrological automaton clock dating to the late 1400s.

A surreal statue honoring Prague's favorite literary son.