The paper deals with the fi rst experience of developing a parallel corpus featuring translation(s) of Old East Slavic resp. Middle Russian texts into a modern language. Within such corpus, a translation serves as a full-fl edged searchable textual element with its own annotation. The resource can function as a tool for studying the OES lexicon, grammar and syntax through aligned parallel texts. Birchbark letters may serve as a pilot example of such aligned corpus as linguistically founded translations are already available for them: birchbark letters were translated into Russian by Andrei Zalizniak and into English two alternative translations by Roman Kovalev and Jos Schaeken. The paper envisages some examples examples of how this mechanism can be applied.