From the Wikipedia page 
Passau (German pronunciation: [ˈpasaʊ]' Austro-Bavarian: Båssa) is a town in Lower Bavaria, Germany. It is also known as the Dreiflüssestadt or "City of Three Rivers," because the Danube is joined at Passau by the Inn from the south and the Ilz from the north.
Until 2013, the City of Passau was subdivided into eight statistical districts, which in general coincide with formerly separate municipalities. Since 2013, the city is divided in 16 so-called areas of open council ("Bürgerversammlungsgebiete").