Ouenza, town, northeastern Algeria. It lies in the Medjerda Mountains near the eastern border with Tunisia, about 40 miles (65 km) east-northeast of Aïn Beïda. The nearby Mount Ouenza (4,226 feet [1,288 metres]) is the site of extensive iron-ore deposits, making the town one of Algeria’s leading mining centres. Pop. (2008) 47,312.