Kryptos: The CIA Cipher Hiding in Plain Sight
Kryptos photo via Wikimedia Commons
Kryptos is an encrypted sculpture installed at CIA headquarters in Langley, Virginia. It’s a set of huge copper plates with enciphered text carved into them — for example, one segment reads TWTQSJQSSEKZZWATJKLUDIAWINFBNYP, though it looks a lot nicer in context.
Although the sculpture was installed in 1990, it took until 1999 [...]