Ełk Lake
Ełk Lake is a fresh water lake in the Masurian Lake District of Poland's Warmia-Mazury Province to the west of the town of Ełk. It has had recent pollution challenges. A larger lake in the lake district to the east of the town of Ełk is Selmęt Wielki.
The lake that was created by glacial action during the Pleistocene ice age and has a maximum surface area of. Its mean depth is with as a maximum. It is divided into two distinct parts, the northern and southern, by a narrows spanned by a bridge. Primarily fed by the Ełk River, a right-bank tributary of the Biebrza River from the south west, the lake discharges into Lake Sunowo to its north-west, and the smaller Lake Szarek associated with the village of the same name to its west.