This memorial commemorating fallen Swiss Guards of the French Revolution has been called the saddest stone in the world.

Mysterious 500-year-old tapestries depict a unicorn hunt.

Elevated freight railway turned wildly successful urban park.

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

This spooky statue sits outside a famous Prague theater.

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

This automated sculpture of two men peeing will spell out text messages with their micturition.

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

A mocking tribute to the past and modern leadership of Prague.

A bust of Franz Kafka spins in pieces, reflecting the writer's inner torment.

Macabre astrological automaton clock dating to the late 1400s.