Mrągowo (until 1947 Polish: Żądźbork; German: Sensburg (help·info), Lithuanian: Senpilė) is a town in the Warmian-Masurian Voivodeship of northeastern Poland, the capital of Mrągowo County and the seat (though not part of) the Gmina Mrągowo. It is located within the Masurian Lake District, about 60 km (37 mi) east of Olsztyn.