“Kryptos is an encrypted sculpture by American artist Jim Sanborn (Wikipedia page ) located on...Kryptos
“A'BIGOT' list is a list of personnel possessing appropriate security clearance and who are...BIGOT and crosswords
“From the longer Wikipedia page  - there is more information on the Russian and Ukrainian...Book of Veles
“The D-Day carrier pigeon cipher is an encrypted message found in 2012 attached to the skeleton...D-Day carrier pigeon cipher
“From the Wikipedia page  The RSA Secret-Key Challenge consisted of a series of cryptographic...RSA Secret-Key Challenge
“The Rohonc Codex is a set of writings in an unknown writing system. This codex is also referred...Rohonc Codex
Pages in category "20th century"
The following 146 pages are in this category, out of 146 total.