Iowa - Role: Building
| Lake City Public Library |
| Lake, John, House |
| Lakeside Ballroom |
| Lamberson, Jack, House |
| Lamb, Lafayette, House |
| Lancaster School |
| Land and Loan Office Building |
| Lane, Lucius and Maria Clinton, House |
| Lane, Samuel M., House |
| Langworthy House |
| Lansing Fisheries Building |
| Lansing Stone School |
| La Porte City Station |
| LaPorte City Town Hall and Fire Station |
| Larsen, Chris, House |
| Larsen, Jens T., House |
| Lattner Auditorium Building |
| Laurens Carnegie Free Library |
| LeClaire, Antoine, House |
| Lee, Captain Daniel S. and Fannie L. (Brooks), House |
| Lee County Courthouse |
| Leeds Junior High School |
| Leith, Doctor Alexander R. (A.R.) and Louisa J., House |
| Le Mars Central High School |
| Le Mars Public Library |
| Lenox Hotel |
| Lenox Round Barn |
| Lenox Township Church of the New Jersalem |
| Lerch, Gustov C., House |
| Lesinger Block |
| Letovsky-Rohret House |
| Lewelling, Henderson, House |
| Lewis Hotel |
| Lewis System Armored Car and Detective Service Building |
| Lexington, The |
| Liberty Building |
| Liberty Hall |
| Lime Springs Mill Complex |
| Lincoln Elementary School |
| Lincoln Hotel |
| Lincoln School |
| Lincoln School |
| Lincoln School |
| Lincoln Township Mausoleum |
| Linden Flats |
| Lindsay, James E., House |
| Linograph Company Building, The |
| Linsay House |
| Lippert House |
| Lippincott, John, House |
| Lisbon Methodist Church |
| Littig Brothers/Mengel & Klindt/Eagle Brewery |
| Littig, John, House |
| """Lockkeeper's"" House" |
| Locust School |
| Loetscher, T. Ben, House |
| Logan Center School No.5 |
| Long, J. G. and Regina, House |
| Lord, Richard T. C., and William V. Wilcox House |
| Loucks Grove Church |
| Louden Machinery Company |
| Louden Monorail System in the Auto Repair Shop |
| Louden, R. B. and Lizzie L., House |
| Louden, R. Bruce and May W., House |
| Louden, R.R., and Antoinette, House |
| Louden, William and Mary Jane, House |
| Louisa Building |
| Louisa County Courthouse |
| Louis F. and Emma M. (Edler) Wohlert House-Emma Wohlert Maternity Home |
| Lubben, Henry, House, Smokehouse and Springhouse |
| Lucas County Courthouse |
| Luedtke, August and Vera, Barn |
| Lueschen, John, House |
| Lustron Home #02102 |
| Lustron House #02437 |
| Luther A. and Elinore T. Brewer House |
| Luther College Farm |
| Lu Verne City Jail |
| Lynnville Mill and Dam |
| Lyon Block |
| Lyon County Courthouse |
| Maas Commercial Building |
| MacDonald, Gilmour B. and Edith Craig, House |
| Mack-International Motor Truck Corporation Building |
| Macumber, John Andrew and Sara, Ice House |
| Madison County Courthouse |
| Mahaska County Courthouse |
| Mahnke House |
| Maine, The |
| Maish House |
| Malek Theatre |
| Mallet, Joseph, House |
| Manatt, William, House |
| Mann School No. 2 |
| Maple View Sanitarium |
| Maquoketa Company-Clinton Machine Company Administration Building |
| Maquoketa Free Public Library |
| Marble Rock Bank |
| Marion Carnegie Public Library |
| Marion County Courthouse |
Data from United States Park Service and Wikidata
