From Stamps of the World
Czarnków ([ˈt͡ʂarŋkuf]; German: Scharnikau, before 1939: Czarnikau) is a town (11,305 inhabitants in 2013) in Poland in Czarnków-Trzcianka County in Greater Poland Voivodeship, previously in Piła Voivodeship (1975-1998). The town lies on the Noteć river. Because there are many hills around the town, the area is called Szwajcaria Czarnkowska (Czarnków's Switzerland). Historically in the Prussian province Posen.
Postmarks in Poland
Postmarks in Empire of Germany
Postmarks in North German Confederation
Postmarks in Prussia Posen province
CZARNIKAU Kreis used a postal code 293, District BROMBERG.