What Is Cicada 3301? The Unsolved Internet Puzzle
PGP-signed puzzles, physical posters and a runic book that still resists solvers.
2 min read
Summary
What is Cicada 3301? It is the name given to three rounds of highly difficult internet puzzles posted under the label "3301" in January 2012, 2013 and 2014. The first message on 4chan said the organisers were looking for "highly intelligent individuals." Clues used cryptography, steganography, literature and physical posters. Who ran it, and why, has never been publicly confirmed.
How did the first Cicada 3301 puzzle start?
On 4 January 2012 an image posted to 4chan challenged readers to find a hidden message. Solvers found encrypted text, steganography and, later, GPS locations where printed posters with QR codes appeared in several cities. Authenticity was checked with a consistent OpenPGP signature.
What happened in 2013 and 2014?
A second round began on 4 January 2013. Solver Marcus Wanner and others described a private forum stage for people who finished. A third round was announced on Twitter on 4 January 2014 and introduced Liber Primus, a book of pages written in a runic cipher. Large parts of Liber Primus remain unsolved.
What techniques did the puzzles use?
- Image steganography and classical ciphers
- Book codes tied to specific texts
- Telephone recordings and countdown pages
- Real-world posters in multiple countries
- Tor hidden services for later stages
Do we know who created Cicada 3301?
No verified identity has been published. Theories range from a recruitment tool for security work to an alternate-reality game. The group has denied links to unrelated hackers who reused the "3301" name. Its last widely cited PGP-signed message appeared in April 2017, rejecting unsigned puzzles.
FAQ
Is Cicada 3301 solved? Early rounds were completed by solvers. Liber Primus from the 2014 path is largely unsolved.
Was it run by the NSA or CIA? That is speculation. No public proof confirms an intelligence-agency sponsor.
Is it safe to chase old clues? Old puzzles are historical curiosities. Do not trust unsigned copycats or sites asking for money or personal data.
Related
- What is the dead internet theory?
- What is the Mandela effect?
- How to start a faceless YouTube channel
Sources
Lab evidence
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Facts in this draft were checked on 14 Oct 2026 against the sources listed in the body (official records, publishers, encyclopaedias and named news outlets). No original testing or reporting was done; figures are quoted as published by those sources, fiction and folklore are labelled as such, and any estimate or prediction is labelled as such.
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