Feature Name | Class | Elev. meters | County | Latitude DMS | Longitude DMS |
| Surry | Locale | 307 | Greene | 41 52 55 N | 094 11 01 W |
| Surry Post Office (historical) | Post Office | 314 | Greene | 41 52 60 N | 094 11 31 W |
| Susie Sower Park | Park | 286 | Marshall | 42 02 60 N | 092 54 35 W |
| Suspension Bridge | Bridge | 300 | Floyd | 43 04 14 N | 092 41 09 W |
| Sutcliff Woodland | Park | 383 | Guthrie | 41 39 10 N | 094 38 26 W |
| Sutherland | Populated Place | 435 | O'Brien | 42 58 27 N | 095 29 51 W |
| Sutherland (historical) | Locale | 435 | O'Brien | 42 58 30 N | 095 29 53 W |
| Sutherland Family Medicine Center | Hospital | 436 | O'Brien | 42 58 27 N | 095 29 54 W |
| Sutherland Farmers Co-op Elevator | Locale | 445 | O'Brien | 42 59 28 N | 095 29 45 W |
| Sutherland Methodist Church | Church | 440 | O'Brien | 42 58 27 N | 095 30 02 W |
| Sutherland Post Office | Post Office | 436 | O'Brien | 42 58 28 N | 095 29 53 W |
| Sutiff Cemetery | Cemetery | 245 | Johnson | 41 50 30 N | 091 25 29 W |
| Sutliff | Populated Place | 212 | Johnson | 41 50 21 N | 091 23 30 W |
| Sutliff Bridge | Bridge | 204 | Johnson | 41 50 23 N | 091 23 32 W |
| Suttle Creek | Stream | | Allamakee | 43 07 54 N | 091 20 51 W |
| Sutton Cemetery | Cemetery | 367 | Guthrie | 41 48 30 N | 094 36 41 W |
| Sutton Cemetery | Cemetery | 237 | Jackson | 42 10 02 N | 090 42 55 W |
| Sutton Lake Marsh | Swamp | 469 | Osceola | 43 24 14 N | 095 30 48 W |
| Sutton Landing Strip | Airport | 274 | Winneshiek | 43 20 30 N | 091 50 42 W |
| Sutton Post Office (historical) | Post Office | 287 | Warren | 41 24 02 N | 093 29 31 W |
| Swaledale | Locale | 350 | Cerro Gordo | 42 58 38 N | 093 18 58 W |
| Swaledale | Populated Place | 351 | Cerro Gordo | 42 58 43 N | 093 19 01 W |
| Swaledale City Hall | Building | 351 | Cerro Gordo | 42 58 43 N | 093 19 01 W |
| Swaledale Fire Department | Building | 351 | Cerro Gordo | 42 58 43 N | 093 19 01 W |
| Swaledale Post Office | Post Office | 351 | Cerro Gordo | 42 58 43 N | 093 19 01 W |
| Swaledale Public Library | Building | 351 | Cerro Gordo | 42 58 43 N | 093 19 01 W |
| Swaledale United Methodist Church | Church | 351 | Cerro Gordo | 42 58 43 N | 093 19 01 W |
| Swalve Wildlife Management Area | Park | 469 | Osceola | 43 24 57 N | 095 32 47 W |
| Swan | Populated Place | 237 | Marion | 41 27 55 N | 093 18 41 W |
| Swan (historical) | Locale | 237 | Marion | 41 27 55 N | 093 18 41 W |
| Swan Cemetery | Cemetery | 266 | Marion | 41 27 52 N | 093 19 30 W |
| Swan Lake | Lake | 419 | Dickinson | 43 27 33 N | 094 57 05 W |
| Swan Lake | Lake | 384 | Emmet | 43 21 25 N | 094 40 41 W |
| Swan Lake | Lake | 217 | Johnson | 41 46 27 N | 091 40 36 W |
| Swan Lake | Locale | 397 | Emmet | 43 21 50 N | 094 41 11 W |
| Swan Lake | Reservoir | 387 | Carroll | 42 02 01 N | 094 50 25 W |
| Swan Lake (historical) | Lake | 344 | Guthrie | 41 47 57 N | 094 26 01 W |
| Swan Lake (historical) | Lake | 394 | Pocahontas | 42 52 16 N | 094 51 39 W |
| Swan Lake Branch | Stream | | Dallas | 41 47 51 N | 094 07 13 W |
| Swan lake Cemetery | Cemetery | 390 | Emmet | 43 23 06 N | 094 38 18 W |
| Swan Lake Cemetery | Cemetery | 406 | Pocahontas | 42 51 04 N | 094 53 34 W |
| Swan Lake Farmstead Museum | Building | 387 | Carroll | 42 02 30 N | 094 50 31 W |
| Swan Lake State Park | Park | 385 | Carroll | 42 02 26 N | 094 50 37 W |
| Swan Lake State Wildlife Area | Area | 219 | Johnson | 41 46 35 N | 091 40 44 W |
| Swan Lake Village Cemetery | Cemetery | 390 | Emmet | 43 21 38 N | 094 40 46 W |
| Swan Post Office | Post Office | 237 | Marion | 41 27 55 N | 093 18 41 W |
| Swank Church | Church | 188 | Johnson | 41 25 41 N | 091 26 59 W |
| Swank Church Cemetery | Cemetery | 187 | Johnson | 41 25 40 N | 091 26 59 W |
| Swanlake Post Office (historical) | Post Office | 397 | Emmet | 43 21 50 N | 094 41 11 W |
| Swans Cemetery | Cemetery | 274 | Jasper | 41 35 31 N | 092 49 25 W |
| Swanson Ditch | Canal | 324 | Monona | 42 10 36 N | 096 13 24 W |
| Swanson Elevator | Locale | 320 | Story | 42 04 40 N | 093 24 29 W |
| Swanson Wildlife Area | Park | 433 | Osceola | 43 18 53 N | 095 28 41 W |
| Swanton | Populated Place | 300 | Butler | 42 29 60 N | 092 41 33 W |
| Swanton Post Office (historical) | Post Office | 279 | Butler | 42 38 35 N | 092 42 46 W |
| Swanwood | Populated Place | 283 | Polk | 41 39 05 N | 093 35 26 W |
| Swarms Pond | Lake | 161 | Louisa | 41 11 50 N | 091 05 51 W |
| Swea (historical) | Populated Place | 366 | Kossuth | 43 24 53 N | 094 23 01 W |
| Swea City | Locale | 360 | Kossuth | 43 23 08 N | 094 18 35 W |
| Swea City | Populated Place | 360 | Kossuth | 43 23 04 N | 094 18 54 W |
| Swea City City Hall | Building | 359 | Kossuth | 43 23 01 N | 094 18 33 W |
| Swea City Fire Department | Building | 359 | Kossuth | 43 23 01 N | 094 18 33 W |
| Swea City Police Department | Building | 359 | Kossuth | 43 23 01 N | 094 18 33 W |
| Swea City Post Office | Post Office | 359 | Kossuth | 43 23 02 N | 094 18 32 W |
| Swea City Public Library | Building | 359 | Kossuth | 43 23 01 N | 094 18 33 W |
| Swea Post Office (historical) | Post Office | 365 | Kossuth | 43 25 27 N | 094 22 16 W |
| Swea Township Cemetery | Cemetery | 366 | Kossuth | 43 23 44 N | 094 23 08 W |
| Swede Bend Church | Church | 344 | Webster | 42 13 40 N | 093 57 36 W |
| Swede Cemetery | Cemetery | 203 | Des Moines | 40 46 30 N | 091 11 31 W |
| Swede Hollow | Valley | | Lucas | 41 04 59 N | 093 23 32 W |
| Swede Point Park | Park | 302 | Boone | 41 53 10 N | 093 50 51 W |
| Swede Valley Church | Church | 332 | Boone | 41 58 34 N | 094 01 44 W |
| Swede Valley Lutheran Cemetery | Cemetery | 333 | Boone | 41 58 36 N | 094 01 42 W |
| Swedenborg Church | Church | 254 | Iowa | 41 50 51 N | 091 55 44 W |
| Swedesburg | Populated Place | 222 | Henry | 41 06 19 N | 091 32 50 W |
| Swedesburg Cemetery | Cemetery | 222 | Henry | 41 06 21 N | 091 32 44 W |
| Swedesburg Evangelical Lutheran Church | Church | 222 | Henry | 41 06 18 N | 091 32 50 W |
| Swedesburg Post Office (historical) | Post Office | 223 | Henry | 41 06 16 N | 091 32 39 W |
| Swedish Cemetery | Cemetery | 376 | Calhoun | 42 32 33 N | 094 35 58 W |
| Swedish Heritage and Cultural Center | Building | 367 | Montgomery | 40 58 56 N | 095 06 06 W |
| Swedish Heritage Museum | Building | 222 | Henry | 41 06 18 N | 091 32 50 W |
| Swedish Lutheran Church Cemetery | Cemetery | 354 | Webster | 42 13 03 N | 094 06 27 W |
| Swedish Mission Bethany Cemetery | Cemetery | 384 | Pocahontas | 42 36 50 N | 094 40 40 W |
| Sween Cemetery | Cemetery | 275 | Marion | 41 14 16 N | 093 02 01 W |
| Sweeney Chiropractic Clinic | Hospital | 444 | O'Brien | 43 11 07 N | 095 28 16 W |
| Sweeney Creek | Stream | | O'Brien | 43 10 09 N | 095 46 43 W |
| Sweet Cemetery | Cemetery | 215 | Louisa | 41 16 44 N | 091 28 36 W |
| Sweet Home Cemetery | Cemetery | 342 | Decatur | 40 35 40 N | 093 57 23 W |
| Sweet Home Cemetery | Cemetery | 349 | Ringgold | 40 42 52 N | 094 08 56 W |
| Sweet Home Deliverance Church | Church | 287 | Polk | 41 36 15 N | 093 38 46 W |
| Sweet Marsh State Wildlife Management Area | Park | 304 | Bremer | 42 49 33 N | 092 13 54 W |
| Sweet Vale of Avoca Heritage Museum | Building | 347 | Pottawattamie | 41 28 50 N | 095 20 23 W |
| Sweetland (historical) | Locale | 229 | Muscatine | 41 29 36 N | 090 58 07 W |
| Sweetland Center | Populated Place | 229 | Muscatine | 41 29 36 N | 090 58 11 W |
| Sweetland Centre Post Office (historical) | Post Office | 230 | Muscatine | 41 29 35 N | 090 58 15 W |
| Sweetland Creek | Stream | | Muscatine | 41 26 13 N | 090 57 25 W |
| Sweetland Post Office (historical) | Post Office | 229 | Muscatine | 41 29 36 N | 090 58 07 W |
| Sweetland United Methodist Church | Church | 229 | Muscatine | 41 29 33 N | 090 58 07 W |
| Sweezy Cemetery | Cemetery | 256 | Jackson | 42 12 02 N | 090 40 12 W |
| Sweezy Island | Island | 184 | Clayton | 42 41 24 N | 090 58 00 W |
| Swella Clinic of Chiropractic | Hospital | 271 | Winneshiek | 43 17 45 N | 091 47 26 W |
| Swenson Farm Cemetery | Cemetery | 346 | Winneshiek | 43 29 30 N | 091 37 21 W |
| Swensrud Park | Park | 363 | Worth | 43 26 34 N | 093 13 28 W |
| Swensrud School Museum | Building | 375 | Worth | 43 26 37 N | 093 13 10 W |
| Swift Slough | Channel | 158 | Des Moines | 40 53 08 N | 091 01 56 W |
| Swift Slough | Gut | 184 | Clayton | 42 46 59 N | 091 05 12 W |
| Swim Chiropractic Care Center | Hospital | 247 | Mahaska | 41 17 50 N | 092 37 51 W |
| Swinney Cemetery | Cemetery | 258 | Davis | 40 50 00 N | 092 22 41 W |
| Swisher | Locale | 241 | Johnson | 41 50 45 N | 091 41 36 W |
| Swisher | Populated Place | 241 | Johnson | 41 50 44 N | 091 41 35 W |