Azerbijan, or Aderbeitzan (anc. Atropatene), a province of Armenian Persia comprised within the old limits of Media. It lies S. of the river Aras, and is cut off by a narrow strip of Russian territory from the Caspian. Its area is 25,280 square miles, and its population about two millions. The surface is very mountainous - the peak of Savalany attaining over 12,000 feet, but the plains are very fertile. Numbers of cattle, sheep, and horses are bred and reared. There is also great mineral wealth of which but trifling use is made, and naphtha is abundant. Leather-dressing is the chief industry, but velvets, carpets, woollen fabrics, and cutlery are manufactured. The great salt lake of Urumiyah occupies a large space to the west and receives several considerable rivers. Tabruz, the capital, is situated almost in the centre, to the N. of the Sahund mountains.