Wichita, the largest city in Kansas and the seat of Sedgwick County, is the focus of a metropolitan statistical area that includes Butler and Sedgwick counties. The city's history reflects the major stages of western U.S. development. The primary stop on the Chisholm Trail, Wichita flourished first as a cattle town, then as a rail link and milling center for Kansas grain. Prosperity continued with the discovery of oil near the city limits. Today Wichita, three-time winner of the National Civic League's All-America City Award, is an important technology center, particularly in the aviation industry.