Hańcza (Polish: [ˈxaɲ.t͡ʂa] ⓘ; Lithuanian: Ančia) is a lake in Suwałki Region, Podlaskie Voivodeship, Poland.

Melting ice left behind various landforms, including glacial troughs, which filled with water, creating lakes.

These waters flowed under immense pressure beneath the ice sheet, carving deep channels into the substrate.

Hańcza has a characteristic elongated shape, typical of ribbon lakes, indicating its glacial origin.

The region is predominantly composed of metamorphic and igneous rocks, particularly in the northern part, where gneisses and granites are found.