Linn County is a county located in the U.S. state of Iowa. As of the 2020 census, the population was 230,299, making it the second-most populous county in Iowa. The county seat is Cedar Rapids. Linn County is named in honor of Senator Lewis F. Linn of Missouri. Linn County is included in the Cedar Rapids, IA Metropolitan Statistical Area.

Iowa is a landlocked state in the upper Midwestern region of the United States. It borders the Mississippi River to the east and the Missouri River and Big Sioux River to the west; Wisconsin to the northeast, Illinois to the east and southeast, Missouri to the south, Nebraska to the west, South Dakota to the northwest, and Minnesota to the north.