Mosna, Poland  Mosna () is a village in the administrative district of Gmina Czersk, within Chojnice County, Pomeranian Voivodeship, in northern Poland. It lies approximately south-east of Czersk, east of Chojnice, and south-west of the regional capital Gdańsk. For details of the history of the region, see "History of Pomerania". The village has a population of 94.