Around 100,000 bodies are buried below the medieval headstones, many of which mark graves with multiple bodies stacked up to 12 deep.

Synagogue built from the stones of Solomon's temple contains the golem of Prague.

A surreal statue honoring Prague's favorite literary son.

A plaque marks the spot where the saint was shoved off the Charles Bridge and into the river.

This spooky statue sits outside a famous Prague theater.

Macabre astrological automaton clock dating to the late 1400s.

The slender brass strip in Prague's Old Town Square was used to tell time from 1652 to 1918.

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

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

The most loyal of little dogs, or a Victorian era publicity stunt?

A sweet symbol marks the place where torturous executions were once carried out.

This pub was 238 years old when it decided to revamp its image: It started serving Thai food.

This medieval sanctuary's tree-framed door looks like a portal to a mythical realm.

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

A commemorative plaque at the door pays tribute to an "American Patriot" known for his betrayal.

Never actually a tree at all, this spot was the site of London's public hangings for nearly 600 years.

The first place where the scientific innovation known as radar was first demonstrated in Britain.

Now harmless, this looming post struck fear into the heart of medieval troublemakers.

A musical instrument played by the sea.

A unique flight of canal locks that owe their form to 19th-century cost-saving measures.

Brass cobblestones mark the places where individual Holocaust victims were taken from their homes.

This hidden alley near the location of Rome's first theater was the site of a curious miracle.

This ritzy Italian market is built around a statue of an unforgiven heretic who was burned for his belief in an endless universe.

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."