Beinecke Rare Book and Manuscript Library of Yale University published the Voynich manuscript online, which scientists assert (with 95% confidence) was made in the 15th century. It has about 240 pages of text and illustrations that have never been deciphered as to their meaning. The writing looks like a language, the illustrations look like plants, biological or cosmological diagrams but with no ...meaning. In the context of the 21st century this clearly is a work of art.
Voynich manuscript