Upper Austria, Ger. Oberösterreich, province (1991 pop. 1,333,480), 4,625 sq mi (11,979 sq km), NW Austria. Linz is the capital. Bordering on Germany in the west and the Czech Republic in the north, the province is predominantly hilly. It is drained by the Danube River and three of its tributaries, the Inn, the Enns, and the Traun, and includes a large part of the Salzkammergut resort area. Agriculture is still an important branch of the economy, with dairy farming and cattle breeding being the most important. There are salt mines, oil wells, and gas fields in the region and a large number of electric power stations. Industry is centered at Linz, Steyr, the Traun and Ager valleys, and Ranshofen. Manufactures include chemicals, iron and steel, aluminum, processed foods, motors, trucks, ships, beer, agricultural machinery, sports equipment, shoes, optical utensils, and textiles. The area of Upper Austria was included in the Roman province of Noricum. In 1156 it was made a duchy by Frederick I and given to the Babenberg dukes of Austria. The province was invaded by the Turks in the 16th cent. It was a site of battles during the Thirty Years War (1618–48) and during the campaigns of Napoleon I.