The Oenus (Ancient Greek: Οἰνοῦς, Greek: Οινούντας - Oinountas, also called Kelefina) is a river in the Peloponnese peninsula, southern Greece. It rises in the watershed of Mt. Parnon, and, after flowing in a general southwesterly direction, falls into the Eurotas, at the distance of little more than a mile from Sparta.