Kryptos is an encrypted sculpture installed in the courtyard of CIA headquarters in Langley, Virginia. Created by American artist Jim Sanborn, it features 870 characters of coded text punched through copper plates, split into four distinct sections. Three of those sections have been solved. The fourth, containing just 97 characters, has resisted every attempt at decryption for over 35 years and remains one of the most famous unsolved codes in the world.
The Sculpture Itself
Kryptos (Greek for “hidden”) is more than a slab of text. It’s a sprawling installation that begins at the entrance to the CIA’s New Headquarters building, where two constructions of red granite and copperplate flank the walkway from the parking deck. In the courtyard, a calm reflecting pool sits between layered granite slabs surrounded by tall grasses. The centerpiece is an S-shaped copper screen, designed to look like a piece of paper curling out of a computer printer, supported by a large piece of petrified wood and encircling a bubbling pool of water.
Sanborn built the sculpture entirely from materials native to the United States: polished red granite, quartz, copperplate, lodestone (a naturally magnetized rock paired with a compass rose), and petrified wood. The petrified tree symbolizes the trees that once stood on the site and, more broadly, the wood-based materials on which written language has historically been recorded. Every element ties back to the theme of information, how it’s stored, hidden, and transmitted.
The Three Solved Sections
Of the 870 encoded characters on the copper plates, the first 773 are divided into three sections known as K1, K2, and K3. All three were cracked by the mid-1990s, though the solutions weren’t publicly confirmed until years later.
K1: A Poetic Riddle
The first section uses a Vigenère cipher, a centuries-old encryption method that shifts letters based on a keyword. In this case, the keywords are PALIMPSEST and KRYPTOS. The decoded message reads: “Between subtle shading and the absence of light lies the nuance of iqlusion.” The deliberate misspelling of “illusion” as “iqlusion” has fueled debate about whether it’s an intentional clue or a simple encoding error. The message itself reads like a meditation on secrecy, fitting for a sculpture at the heart of an intelligence agency.
K2: Coordinates and a Mystery
The second section also uses a Vigenère cipher, this time with the keywords ABSCISSA (a mathematical term for a point on a graph) and KRYPTOS. Its decoded text is far more narrative and spy-flavored:
“It was totally invisible. How’s that possible? They used the Earth’s magnetic field. The information was gathered and transmitted underground to an unknown location. Does Langley know about this? They should. It’s buried out there somewhere. Who knows the exact location? Only WW. This was his last message.”
The passage then gives a set of geographic coordinates: 38 degrees, 57 minutes, 6.5 seconds north; 77 degrees, 8 minutes, 44 seconds west. Those coordinates point to a spot very close to the Kryptos sculpture itself on the CIA grounds. The identity of “WW” has never been officially confirmed, though many enthusiasts believe it refers to William Webster, who was CIA director when the sculpture was installed.
K3: An Echo of King Tut’s Tomb
The third section uses a different technique entirely: a route transposition layered with a keyed columnar transposition, both organized around the numerical key 0362514 (derived from KRYPTOS). The decoded text is a paraphrase of archaeologist Howard Carter’s famous account of opening King Tutankhamun’s tomb in 1922:
“Slowly, desperately slowly, the remains of passage debris that encumbered the lower part of the doorway was removed. With trembling hands I made a tiny breach in the upper left-hand corner and then widening the hole a little I inserted the candle and peered in. The hot air escaping from the chamber caused the flame to flicker but presently details of the room within emerged from the mist. Can you see anything?”
Like K1, this section contains intentional misspellings (“desparatly” instead of “desperately”), which may serve as additional clues for the unsolved fourth section.
K4: The Unsolved 97 Characters
The final 97 characters of Kryptos have defeated cryptographers at the CIA, the NSA, and countless amateur codebreakers since the sculpture’s installation. No one has publicly produced a verified solution. The encryption method is unknown, and the brevity of the passage makes statistical analysis extremely difficult. With so few characters, there simply isn’t enough data to identify reliable patterns.
Sanborn has released a handful of clues over the years. He confirmed that the word BERLIN appears in the decrypted text at a specific position, and later revealed that CLOCK also appears, forming the phrase BERLIN CLOCK. In 2024, Popular Mechanics reported that Sanborn released what he called his final clues, confirming that the Berlin Clock refers to the World Clock in Berlin, a landmark that served as a gathering place for the crowds that brought down the Berlin Wall. He also confirmed that the word NORTHEAST appears in the solution.
These clues narrow the possibilities but haven’t been enough. The challenge isn’t just figuring out the encryption method. It’s that K4 may use a technique that depends on information embedded elsewhere in the sculpture, in the compass rose, the lodestone, or the physical layout of the courtyard itself. Sanborn has said that solving K4 requires understanding the entire installation, not just the text on the copper screen.
Why It Still Matters
Kryptos sits at a unique intersection of art, cryptography, and Cold War symbolism. It was designed to remind the people who walk past it every day, intelligence officers, that some secrets resist even the most sophisticated tools. For everyone else, it’s become a global puzzle, the subject of novels (Dan Brown referenced it in “The Lost Symbol”), online communities, and decades of collaborative codebreaking attempts.
The sculpture also works as a layered metaphor. Its materials tell a story about how information exists in the physical world: in magnetic fields (the lodestone), in the rings of ancient trees (the petrified wood), in the structure of stone (the granite and quartz). The coded text is the most obvious puzzle, but the entire courtyard is designed to make you think about what’s hidden in plain sight.
Sanborn, now in his late 70s, has said he worries the final section may not be solved in his lifetime. He’s arranged for the answer to be revealed after his death if no one cracks it. Until then, K4’s 97 characters remain the most famous unsolved cipher in the world.