The Algonquin Mill at Petersburg was obtained by the Carroll County Historical Society in 1969 and was restored by volunteer labor. This steam powered flouring mill produces stone ground flours and corn meal for sale to the public every Thursday from 9am - 3pm. In order to raise money for restoration and operation, a Fall Festival was started in 1971 and has grown to a three-day event drawing upwards of 75,000 people. The profits from the Fall Festival have been reinvested in Carroll County, in part by purchasing the adjoining farm. Today, the Algonquin Mill Farm Complex is comprised of the Mill, farm house, several barns and storage buildings, craft building and farm museum, several reconstructed log houses and an award winning arboretum. The Mill is listed in the National Register of Historic Sites.