The deepest (108,5 m) lake in Poland and on the European Lowland. A typical postglacial channel lake with an area of 305 ha, almost 5km long and up to 1 km wide. The shore full of boulders, mostly steep and high, the shoreline with picturesque bays and peninsulas. The bottom carved with trenches, holes and steep hallows – a great attraction for scuba divers. Hańcza is a lake of crystal-clear, cold and well aerated waters. The flora of the lake is sparse. The zooplankton is represented by Scandinavian-baltic species of crustacea. There are 24 species of fish, among them Baltic whitefish (powan), European whitefish (vendace), and such rarities like bullhead, Siberian bullhead, European minnow and spined loach. Lake Hańcza has been a water-landscape reserve since 1963. Near the lake there are a few tourist trails including two educational ones – “ Through the Czarna Hańcza Valley”, “Trees and bushes of the Old Hańcza landed estate park”, a bike trail “Around Lake Hańcza”. Wonderful panoramas of the lake and the western part of the park can be admired from a beauty spot on Mount Leszczynowa (Hazel) in Przełomka.