Mittelmark ( German: Mittelmark - Middle mark) is a historical region in Germany , known as the original territory of the Brandenburg mark since 1417 . The name is presumably related to the geographical location between Altmark (Old Mark, Old Marchia, now in the federal state of Saxony-Anhalt ) and Neumark ( New Mark , New Marchia, now Poland ).
Since 1993, Mittelmark has been used again in the name of the administrative district of Potsdam-Mittelmark , which occupies only part of the former Mittelmark.