At 113.8 square kilometres (43.9 sq mi), Śniardwy is the largest lake in Poland.

[3] Śniardwy was formed by retreating ice sheet and draining floodwaters occurring as the result of ice calving ahead of the receding glacier.

Surrounding settlements include Popielno, Głodowo, Niedźwiedzi Róg, Okartowo, Nowe Guty, Zdęgowo and Łuknajno.

[3] Among the many inlets, two are named as separate lakes: Warnołty and Seksty.

Śniardwy connects with the following lakes: Tuchlin, Łuknajno, Mikołajskie, Roś, Białoławki and Tyrkło.