| Property | Address | City | Date Listed |
|---|---|---|---|
| Antlers Hotel | 1703 Hill Ave. | Spirit Lake | 05/24/07 |
| Clark Gerome House | E of Milford | Milford | 11/09/1977 |
| Gull Point State Park | Area A Off IA 86 on W Shore of W Okoboji Lake | Milford | 11/15/1990 |
| Gull Point State Park | Area B Off IA 86 on W shore of W Okoboji Lake | Milford | 11/15/1990 |
| Iowa Lakeside Laboratory Historic District | IA 86 about 4 mi. N-NW of jct. with US 71 | Milford | 12/23/1991 |
| Mini-Wakan State Park Historic District | 24490 100th St. | Spirit Lake vicinity | 02/17/2010 |
| Okoboji Bridge | 180th Ave. over branch of Little Sioux River | Milford vicinity | 6/25/98 |
| Pikes Point State Park Shelter and Steps | W of jct. of IA 9 and US 71 | Spirit Lake | 11/15/1990 |
| Pillsbury Point State Park | Off US 71 W of Minnewashta Lake | Arnolds Park | 01/12/1993 |
| Spirit Lake Massacre Log Cabin Arnolds Park | W of Estherville on U.S. 71 | Arnolds Park | 04/03/1973 |
| Spirit Lake Public Library | 1801 Hill Ave. | Spirit Lake | 01/24/1980 |
| Trappers Bay State Park Picnic Shelter | N of jct. of IA 219 and IA 9 | Lake Park | 11/15/1990 |