The Crișul Negru (Romanian), (Hungarian: Fekete-Körös) is a river in western Romania (Transylvania) and south-eastern Hungary (Békés County). The river has its source in the western Apuseni Mountains. It flows through the towns Ștei and Beiuș in Romania. Crossing the border of Hungary the river, now called Fekete-Körös, joins the Fehér-Körös a few kilometres north from Gyula to form the Körös river. In Romania, its length is 164 km (102 mi) and its basin size is 3,820 km2 (1,470 sq mi). Part of the water from the river Crișul Repede is diverted towards the Crișul Negru by the Criș Collector Canal.