The Rio del Rey (also called Rio del Ray) is a drainage basin/watershed/estuary located in West Africa within Equatorial Guinea and Cameroon. It is located in the eastern area of the Niger River system. The Cameroon volcanic line separates Rio Del Rey from the Douala basin. Rio del Rey has been described as an estuary in which "the two rivers N'dian and Massake flow out".
References
Rio del Rey Wikipedia(Text) CC BY-SA