You may be aware of Kryptos, the sculpture covered in enciphered text and located outside CIA headquarters (and so not accessible to the general public). Three of the four messages on the sculpture have been decrypted, but the fourth remained obscured. Now the Telegraph reports that the sculptor, Jim Sanborn, who is apparently surprised that the puzzle is unsolved 22 years after the sculpture was created – has offered a clue “by divulging six of the 97 letters in that last phrase”:
On the sculpture, they read NYPVTT. Decoded, they say BERLIN, he disclosed.
The Telegraph quote Sanborn saying:
I never thought that it would take this long. I have tried to narrow the options and offer the Kryptos community some reward for all their attention. There are people out there who have come close to wrecking their lives and careers as a result of their obsession with this.
The full Telegraph article gives an account of the history of the piece and talks to some of those attempting to decrypt the message.
Source: A clue to CIA mystery that has defeated the world’s codebreakers.