Owatonna is a city in Steele County, Minnesota, United States. It is the county seat of Steele County. Owatonna is home to the Steele County Fairgrounds, which hosts the Steele County Free Fair in August. Interstate 35 and U.S. Routes 14, and 218 are three of the main arterial routes in the city. Owatonna was the site of the State Fair and soon the county established its own fair in Owatonna, the Steele County Free Fair or SCFF, the largest free fair in Minnesota.