Kryptos

The box holds the first passage of Kryptos, 63 letters cut into the copper of the sculpture, and the tool decrypts it with the key PALIMPSEST. It reads BETWEEN SUBTLE SHADING AND THE ABSENCE OF LIGHT LIES THE NUANCE OF IQLUSION. The misspelling is in the original; Jim Sanborn has said it's deliberate.

The trick is the Alphabet key setting, set to KRYPTOS. Clear it and the same key gives gibberish, PMJXDSHHZ and so on, because K1 isn't a standard Vigenère cipher. Show the steps works through each letter.

An ordinary Vigenère cipher shifts each letter along A to Z by the matching letter of the key. Kryptos scrambles the alphabet first. Its tableau starts with the word KRYPTOS and then runs through the remaining letters in order, KRYPTOSABCDEFGHIJLMNQUVWXZ, and every letter, of the message and of the key, is counted by its place in that alphabet.

The right-hand panel of the sculpture is that tableau, a block of shifted keyed alphabets cut beside the ciphertext. The second passage uses the same alphabet with the key ABSCISSA. The third is a transposition, a different kind of cipher altogether.

Kryptos was dedicated on 3 November 1990, outside the CIA's headquarters in Langley, Virginia. The first person to announce a solution to K1, K2 and K3 was Jim Gillogly, a computer scientist in California, in 1999. The CIA then said one of its analysts, David Stein, had solved the same three by hand in 1998. In 2000 it emerged that an NSA team led by Ken Miller had got there first, in late 1992.

The fourth passage, 97 characters, has resisted everyone. Sanborn has released four clues. In 2010 he said letters 64 to 69, NYPVTT, decrypt to BERLIN, and in 2014 that letters 70 to 74, MZFPK, give CLOCK. In January 2020 letters 26 to 34, QQPRNGKSS, became NORTHEAST, and that August letters 22 to 25, FLRV, became EAST.

In August 2025 Sanborn announced he would auction the solution. That September the journalists Jarett Kobek and Richard Byrne found the plaintext among papers Sanborn had given to the Smithsonian's Archives of American Art. He confirmed it, said the scraps had been included by mistake, and had the files sealed until 2075. The two didn't publish it. RR Auction sold Sanborn's Kryptos archive for $962,500 that November. The answer exists, but it isn't public.