The Limay River is an important river in the northwestern Argentine Patagonia (the region of Comahue). It is born at the eastern end of the Nahuel Huapi Lake and flows in a meandering path for about 380 km, collecting the waters of several tributaries, such as the Traful River, the Pichileufú and the Collón Curá. It then meets the Neuquén River and together they become the Río Negro.