Jim Sanborn created a sculpture called "Kryptos" that was placed outside the CIA headquarters in 1990.
The statue contains 4 passages, only 3 of which have been deciphered by various intelligence agencies and other cryptanalysts. After erecting the statue, Sanborn claimed that the first 3 passages contained clues to the fourth passage. After it remained unsolved for over a decade, Sanborn gave interviews where he said that William H. Webster, the director of the CIA, had the final solution.
A few years later, however, he corrected the message by saying that Webster did not have the entire solution either. Sanborn did confirm that the second part of the encrypted message reads: “Who knows the exact location? Only WW” where “WW” refers to William Webster.
To this day, the remaining 97 characters of the fourth passage remain unsolved.
The Greek translation of "Kryptos" is "hidden." A fitting title for this mysterious monument.
For more info, read the full article here: The Mysterious Kryptos Sculpture: A CIA Puzzle Unsolved for Decades
Source: Link to reddit user Cleverman72
