>>1342605
>Kryptos by Jim Sanborn
Unsolved: Part 4 of Kryptos (the last 97 characters), as of March 2016, remains unsolved:
OBKR
UOXOGHULBSOLIFBBWFLRVQQPRNGKSSO
TWTQSJQSSEKZZWATJKLUDIAWINFBNYP
VTTMZFPKWGDKZXTJCDIGKUHUAUEKCAR
In November 2010, Sanborn offered a clue, that the ciphertext letters NYPVTT in K4 decrypt to the plaintext letters BERLIN.
In November 2014, Sanborn offered a second clue, that the word after BERLIN is CLOCK
http://elonka.com/kryptos/