Narodowe Archiwum Cyfrowe (English: National Digital Archives) is the national archive of Poland, formed 8 March 2008 from the merger of the Archives of Audio-Visual Records and the State Archives of Poland. It acts as the national archive for Poland and holds the central archives of the Poland government. They are the state official archives and aim to provide digital files as a response to the development of recording, storing and access technologies.

More information on the Wikipedia page [1]

The website is [2] (Polish) and [3] (English).