Aitkin is a city in Aitkin County, Minnesota, United States. It is the county seat of Aitkin County. According to the United States Census Bureau, the city has a total area of 1.7 square miles (4.4 square kilometer), all of it land. The Aitkin Municipal Airport is located at the northeast side of town. U.S. Route 169 and Minnesota State Highways 47 and 210, and County Road 15 are four of the main arterial routes in the city.