Billings, city (1990 pop. 81,151), seat of Yellowstone co., S Mont., on the Yellowstone River, in a valley surrounded by seven mountain ranges; inc. as a city 1885. Founded in 1882 by the Northern Pacific RR, Billings quickly became an important shipping point and fur-trading center. It is the largest city in Montana and a medical, manufacturing, and trade center for the S Montana–N Wyoming region. Manufactures include paper, wood, dairy, and petroleum products; processed foods; and computer equipment. Wheat, sugar beets, livestock, and wool are traded. Rocky Mountain College and Montana State Univ. at Billings are there. Billings is the center of a recreational area and tourism is important; Custer National Forest and Yellowstone National Park are nearby.