Warren County Iowa has 15 places on the National Register of Historic Places including 1 place of National significance and 7 places of Statewide significance. Significant places include Polled Hereford Breed Origin Site, Coal Creek Bridge, Lake Ahquabi State Park, Bathhouse Area (Area B), Lake Ahquabi State Park, Picnic Area (Area A) and Lake Ahquabi State Park, Refectory Area (Area C).
Some of the country's most noteable architects helped create the Warren County places including Ames Central Design Office, Proudfoot & Bird, William T. Proudfoot, Seevers Manufacturing Co., William Wilson Myrick, Eli Myrick, Keffer and Jones and Grahn & Rathurst. Prominent architectural styles found in Warren Country are Gothic, Late Gothic Revival and Other.