The Cestos River is a Liberian river that rises in the Nimba Range of Guinea and flows south along the Côte d'Ivoire border, then southwest through tracks of Liberian rain forest to empty into a bay on the Atlantic Ocean where the city River Cess is located. The Pygmy Hippopotamus (Choeropsis liberiensis) is known to inhabit lands along stretches of the river.[1] It forms the northern third of the international boundary between Liberia and Côte d'Ivoire.