The Cerna is a left tributary of the river Mureș in Transylvania, Romania. Its name both in Romanian and Hungarian languages originates from a Slav language, meaning "black (water)". Its source is in the Poiana Ruscă Mountains. It flows through the town Hunedoara and the villages Gura Bordului, Lunca Cernii de Sus, Lunca Cernii de Jos, Hășdău, Dăbâca, Toplița, Cinciș-Cerna, Teliucu Superior, Teliucu Inferior, Peștișu Mare and Sântandrei. It discharges into the Mureș in Sântuhalm near Deva. Its length is 73 km (45 mi) and its basin size is 727 km2 (281 sq mi).