midwestern states State of Iowa A state located in the Midwestern region of the United States of America. Iowa is bordered by the Mississippi River on the east; the Missouri River and the Big Sioux River on the west; the northern boundary is a line along 43 degrees, 30 minutes north latitude. The southern border is the Des Moines River and a line along approximately 40 degrees 35 minutes north. LanguaL curation note: US FDA 1995 Code: US19 iowa State of Iowa A state located in the Midwestern region of the United States of America. Iowa is bordered by the Mississippi River on the east; the Missouri River and the Big Sioux River on the west; the northern boundary is a line along 43 degrees, 30 minutes north latitude. The southern border is the Des Moines River and a line along approximately 40 degrees 35 minutes north. LanguaL curation note: US FDA 1995 Code: US19 iowa