Codes Nobody Can Crack

Ranked by years unsolved: a 600-year-old book, a still-secret sculpture, and a cipher pointing to buried treasure.

The top 3

1. The Voynich Manuscript: Vellum carbon-dated to 1404-1438; ~240 pages of unknown script that no cryptographer, linguist, or AI has ever decoded.
2. Kryptos K4: Sculptor Jim Sanborn's 1990 puzzle hides 4 passages; three were solved, but the final 97 characters remain uncracked.
3. The Beale Ciphers: Three codes from an 1885 pamphlet; only the middle one was cracked, describing buried gold and silver worth tens of millions.

Sources

• Beinecke Library, Yale
• Encyclopaedia Britannica

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