a lake in northeastern Poland, one of the Masurian lakes. Situated at an elevation of 116 m, the lake covers an area of 104 sq km and has a maximum depth of 40 m.
Lake Mamry lies in a depression between ancient moraine ridges. It consists of several pools joined by channels and has numerous sandbars and islands. In the north it drains into the Pregolia river system and in the south into the Vistula river system. The lake is used for shipping and fishing and is a popular tourist spot.