From the Wikipedia page 
Poznań County (Polish: powiat poznański) is a unit of territorial administration and local government (powiat) in Greater Poland Voivodeship, west-central Poland. It came into being on January 1, 1999, as a result of the Polish local government reforms passed in 1998. Its administrative seat is the city of Poznań, although the city is not part of the county (it constitutes a separate city county). The county's administrative offices (starostwo powiatowe) are in the Jeżyce neighbourhood of Poznań.
Apart from the city of Poznań, Poznań County is also bordered by Oborniki County and Wągrowiec County to the north, Gniezno County and Września County to the east, Środa Wielkopolska County to the south-east, Śrem County and Kościan County to the south, Grodzisk Wielkopolski County and Nowy Tomyśl County to the west, and Szamotuły County to the north-west.