Polish army, which camped along northern bank of the Notec river, concentrated on May 3 in Pila.
The waterways from the German-Polish border (Oder River, through the Warta, Brda and Noteć rivers, Bydgoszcz Canal, Vistula River, Narew River, Bug River) once used to link the Belarus and Ukrainian inland waterways via Mukhavets River, Dnieper–Bug Canal, Pripyat River and Dnieper River), thus connecting north-western Europe with the Black Sea.
The borders of Kujawy spread out to the west from Koronowo and Nakło to the Noteć River where they turn west, cross Trląg Lake, and on to Strzelneński Forest, reaching Skulski Lake and the upper Noteć River.