Voynich manuscript

 

The Voynich manuscript is an illustrated codex hand-written in an unknown writing system, that got it's name after Wilfrid Voynich, the Polish book dealer who acquired it in 1912. Many cryptographers have studied this volume but so far no one has reached any conclusion to what it is. 

It looks like a herbal catalogue, but many species are unknown. It also seems to have some sort of recipes and even astronomical information. Whatever it contains it is still one the greatest mysteries of human history.

Of course it would always be fun if it ended up being the work of a 14th Century troll.