The Voynich manuscript, described as "the world's most mysterious manuscript", is a work which dates to the early 15th century.
Some pages are missing, but the current version comprises about 240 vellum pages, most with illustrations. Much of the manuscript resembles herbal manuscripts of the time period, seeming to present illustrations and information about plants and their possible uses for medical purposes. However, most of the plants do not match known species, and the manuscript's script and language remain unknown and unreadable.
As yet, it has defied all decipherment attempts.