JAEN, a province of Andalusia, Spain, lying between N. Lat. 37. 30. and 38. 40., and W. Long. 2. 50. and 4. 20; and bounded N. by the province of Cuidad-Real, E. by Albacete and Granada, S. by Granada, and W. by Cordova. It is about 80 miles in length from E. to W., by about 70 in average breadth; area 4445 square miles. It is surrounded on every side by lofty mountains, which almost exclude it from communication with the surrounding provinces. Its surface is a constant alternation of hills and valleys, the latter being well watered and fertile, whereas the former yield little except some pasture for sheep, which come here in the winter season from the more northern provinces. Agriculture is in a very backward state, so that, notwithstanding the great fertility, the quantity of grain produced does not meet the amount consumed in the province. The Guadalquivir, with its affluents, drains the entire province. Jaen was celebrated for its mineral productions even in the time of the Romans, and at present its lead and iron mines are extensively wrought. The Moorish kingdom of Jaen was not so extensive as the modern province. Pop. (1849) 307,410. See ANDALUCIA and SPAIN.