Ain, one of the Eastern departments of France, lying between Jura, Saone-et-Loire, and Rhone to the N. and W., Here to the S., and Savoie and Switzerland to the E. Its greatest length and breadth are 52 miles, and its area 2,241 square miles. Mountainous in the E., the country trends into level plains to the W. and S.W., and is watered by the Rhone and its affluents, the Ain and the Saone. The valleys and plains are fertile, producing all kinds of cereals, fruits, and wine. On the higher slopes are valuable forests, and the mountains are rich in such products as potter's clay, building and lithographic stone, asphalt, and iron. Bourg is the chief town, and Belley is the seat of a bishopric.