Sculpture outside the CIA

heard abt it on KERA yestarday...

Solving the Enigma of Kryptos from wired news
"it's been nearly 15 years since Sanborn installed the 12-foot-high, verdigrised copper, granite and wood sculpture inscribed with four encrypted messages at the CIA's Langley, Virginia, headquarters in 1990. And it's been seven years since anyone made progress at cracking its code."

Cracking the Code of a CIA Sculpture from the washington post
"It had reached the point that David Stein was seeing the letters in his head before drifting off to sleep at night. Arrayed in seemingly meaningless order on the copper sides of "Kryptos," an oddly powerful sculpture at the headquarters of the Central Intelligence Agency, they had guarded a secret since the artwork was dedicated in October 1990. "

also related to the book "da vinci code" due to which this has gotten so much popularity.

photo of the sculpture Kryptos