Arkansas City is a city in Cowley County, Kansas, United States, situated at the confluence of the Arkansas and Walnut rivers in the southwestern part of the county. As of the 2010 census, the city population was 12,415. The name of this city is not pronounced like the nearby state of Arkansas, but rather as (the final "s" is pronounced). Over the years there has been much confusion about the regional pronunciation of "Arkansas," which locals render as rather than.