SIOUX CITY, a city of the United States, the capital of Woodbury county, Iowa, lies 156 miles north-west of Des Moines, on the sloping banks of the Missouri river. It is a great railway centre (Chicago, Milwaukee, and St Paul Railway, Sioux City and Pacific Railway, &c.), has an extensive trade, and contains an opera house, foundry and machine shops, pork-packing factories, and mills. The population of the city (which was laid out in 1854 and incorporated in 1857) was 3401 in 1870 and 7366 in 1880 (township 7845).