The river Nervión runs through the city of Bilbao, Spain into the Bay of Biscay. It is also known as ría de Bilbao/Bilboko itsasadarra ("Bilbao estuary") on its final tract. Some call it Ibaizabal ("wide river") but others are of the opinion that Ibaizabal is just one of the smaller rivers running into Nervion.