Postcard-Arnsberg-bar

In 1901 an unknown person sent an encrypted postcard from Iserlohn, Germany, to nearby Arnsberg. Can a reader decipher it?

Bauer-Zodiac-bar

At the HistoCrypt in Uppsala, Craig Bauer gave a talk about famous cryptograms. Among other things, he defended his solution of the second Zodiac Killer cryptogram, which was heavily criticized by the readers of this blog.

Catokwacopa-2-bar

Two encrypted newspaper advertisements from 1875 are still unsoved. Is the first one the key to the second?

Maskenmann-NN-bar

In the intro of the German TV film “Im Namens meines Sohnes” a message is hidden. It is easy to solve.

Olympiad-2017-bar

Here’s a nice crypto challenge I found in a paper about the Fourth International Students’ Olympiad in Cryptography. Can you solve it?

Dog-Tag-Cryptogram-bar.jpg

A dog tag introduced by a Reddit reader bears an inscription that looks like encrypted text. Can a reader solve this cryptogram?

MayMystery-bar

For almost 40 years, an unknown person has published cryptic advertisements in a US university newspaper. It is still unknown who is behind this game.

Donald-Duck-Code-2-bar

A Donald Duck comic story, which was recently republished in a German Disney magazine, contains an encrypted message. The solution, if it exists, appears to be unknown. Can a reader break this cryptogram?

Rohonc-Codex-Tokai-Kiraly-bar

The Rohonc Codex, one of the world’s most famous crypto mysteries, appears to have been solved. Here are the details about the solution.

Rohonc-Codex-solved-bar

The Rohonc Codex, one of the world’s most famous crypto mysteries, appears to have been solved. And yes, I believe this solution is correct.