Kryptos is a sculpture that can be found at the CIA office located in Langley, Virginia, United States. Since its inception, has been much speculation and has become a concern of every CIA employee and various code breakers. The sculpture contains about 869 characters, but the sculptor, James Sanborn, released information that the letters meant in the main code were missing. So the total is 870 characters.
The first person who said managed to solve 3 parts of the code, in 1999, managed to interpret 768 characters. However, the remaining 97 (98) characters are still unbreakable today. This is also the same part of making the government code breaker stuck.