Novgorod Codex
The Novgorod Codex (Russian: Новгородский кодекс, romanized: Novgorodskij kodeks) or the Novgorod Psalter (Новгородская псалтирь, Novgorodskaja psaltir') is the oldest-known book of the Kievan Rus', unearthed on 13 July 2000 in Veliky Novgorod, Russia. It is a palimpsest consisting of three bound wooden tablets containing four pages filled with wax, on which its former owner wrote down dozens, probably hundreds of texts during two or three decades, each time wiping out the preceding text.