BONA (BONE), a seaport of Algeria, in 36 deg. 53' N., 7 deg. 46' E., on a bay of the Mediterranean, chief town of an arrondissement in the department of Constantine, 220 m. by rail W. of Tunis, and 136 m. N.E. of Constantine. The town, which is situated at the foot of the wooded heights of Edugh, is surrounded with a modern rampart erected outside the old Arab wall, the compass of which was found too small for its growth. Much of the old town has been demolished, and its general character now is that of a flourishing French city. The streets are wide and well laid out, but some are very steep. Through the centre of the town runs a broad tree-lined promenade, the Cours Jerome-Bertagna, formerly the Cours National, in which are the principal buildings --theatre, banks, hotels. At its southern end, by the quay, is a bronze statue of Thiers, and at the northern end, the cathedral of St Augustine, a large church built in quasi-Byzantine style. In it is preserved a relic supposed to be the right arm of St Augustine, brought from Pavia in 1842. The Grand Mosque, built out of ruins of the ancient Hippo, occupies one side of the chief square, the Place d'Armes. There are barracks with accommodation for 3000 men, and civil and military hospitals. The Kasbah (citadel) stands on a hill at the north-east of the town. The inner harbour, covering 25 acres, is surrounded by fine quays at which vessels drawing 22 ft. can be moored. Beyond is a spacious outer harbour, built 1857-1868 and enlarged in 1905-1907. Bona is in direct steamship communication with Marseilles, and is the centre of a large commerce, ranking after Algiers and Oran alone in Algeria. It imports general merchandise and manufactures, and exports phosphates, iron, zinc, barley, sheep, wool, cork, esparto, &c. There are manufactories of native garments, tapestry and leather. The marshes at the mouths of the Seybuse and Bujema rivers, which enter the sea to the south of Bona, have been drained by a system of canals, to the improvement of the sanitary condition of the town, which has the further advantage of an abundant water supply obtained from the Edugh hills. There are cork woods and marble quarries in the vicinity, and the valley of the Seybuse and the neighbouring plains are rich in agricultural produce. The population of the town of Bona in 1906 was 36,004, of the commune 42,934, of the arrondissement, which includes La Calle (q.v.) and 11 other communes, 77,803.