Stephenson County
- Freeport, Carnegie Library, 314 West Stephenson Street (covenant)
- Freeport vicinity, Pecatonica River Bridge, spanning Pecatonica River at Winnesheik Road (HAER IL-9)
- Lena, Lena Milling Company (HIER SH-2007-1)
- Lena vicinity, Stone Octagon House (HABS IL-179)
- Rock City vicinity, North Kinney Road Bridge, spanning Brown Creek (HAER IL-129)
- Rural Stephenson County, Gerke Bridge (HIER SH-1996-1)