Feature Name | Class | Elev. meters | County | Latitude DMS | Longitude DMS |
| Lamoille Congregational Church | Church | 304 | Marshall | 42 01 55 N | 093 02 21 W |
| Lamoni | Populated Place | 343 | Decatur | 40 37 22 N | 093 56 03 W |
| Lamoni (historical) | Locale | 342 | Decatur | 40 37 20 N | 093 56 02 W |
| Lamoni Chiropractic Center | Hospital | 343 | Decatur | 40 37 17 N | 093 55 59 W |
| Lamoni City Hall | Building | 342 | Decatur | 40 37 24 N | 093 56 06 W |
| Lamoni Fire Department | Building | 347 | Decatur | 40 37 23 N | 093 55 59 W |
| Lamoni Golf and Country Club | Locale | 342 | Decatur | 40 36 35 N | 093 55 13 W |
| Lamoni High School | School | 347 | Decatur | 40 37 28 N | 093 56 10 W |
| Lamoni Municipal Airport | Airport | 343 | Decatur | 40 38 00 N | 093 54 08 W |
| Lamoni Nursing and Rehabilitation Center | Hospital | 346 | Decatur | 40 37 20 N | 093 55 24 W |
| Lamoni Police Department | Building | 347 | Decatur | 40 37 23 N | 093 55 59 W |
| Lamoni Post Office | Post Office | 348 | Decatur | 40 37 27 N | 093 55 57 W |
| Lamoni Public Library | Building | 348 | Decatur | 40 37 25 N | 093 55 57 W |
| Lamont | Populated Place | 317 | Buchanan | 42 35 55 N | 091 38 32 W |
| Lamont (historical) | Locale | 317 | Buchanan | 42 35 55 N | 091 38 41 W |
| Lamont Creek | Stream | | Buchanan | 42 35 52 N | 091 37 48 W |
| Lamont Elevator | Locale | 317 | Buchanan | 42 35 57 N | 091 38 36 W |
| Lamont Post Office | Post Office | 317 | Buchanan | 42 35 58 N | 091 38 31 W |
| Lamont Public Library | Building | 317 | Buchanan | 42 35 58 N | 091 38 31 W |
| Lamplighter Villa | Populated Place | 261 | Black Hawk | 42 32 32 N | 092 25 11 W |
| Lamprecht Cemetery | Cemetery | 277 | Tama | 42 04 47 N | 092 18 31 W |
| Lamps Pond | Reservoir | 222 | Scott | 41 36 19 N | 090 45 30 W |
| Lamson Mobile Home Park | Populated Place | 254 | Mahaska | 41 18 10 N | 092 39 46 W |
| Lamson Woods State Preserve | Park | 220 | Jefferson | 40 59 35 N | 091 56 33 W |
| Lancaster | Locale | 236 | Keokuk | 41 16 31 N | 092 10 01 W |
| Lancaster Christian Church | Church | 234 | Keokuk | 41 16 30 N | 092 09 41 W |
| Lancaster Post Office (historical) | Post Office | 235 | Keokuk | 41 16 32 N | 092 09 54 W |
| Land O'Lakes Elevator | Locale | 351 | Cerro Gordo | 42 58 43 N | 093 19 01 W |
| Land of Two Waters | Park | 360 | Worth | 43 21 60 N | 093 11 36 W |
| Lande River Conservation Wildlife Area | Park | 374 | Winnebago | 43 26 30 N | 093 35 31 W |
| Landis Post Office (historical) | Post Office | 359 | Taylor | 40 37 15 N | 094 50 01 W |
| Landmark Baptist Church | Church | 368 | Woodbury | 42 30 02 N | 096 24 05 W |
| Landmark Baptist Mission | Church | 332 | Harrison | 41 38 40 N | 095 47 15 W |
| Landmark Church of God | Church | 257 | Mahaska | 41 17 35 N | 092 38 22 W |
| Landmark Missionary Baptist Church | Church | 206 | Scott | 41 27 52 N | 090 43 39 W |
| Landphere Creek | Stream | | Butler | 42 39 17 N | 092 38 23 W |
| Landscape Architecture Building | Building | 287 | Story | 42 01 40 N | 093 38 36 W |
| Landsmeer Golf Club | Locale | 423 | Sioux | 43 00 30 N | 096 02 44 W |
| Lanesboro | Populated Place | 348 | Carroll | 42 11 04 N | 094 41 29 W |
| Lanesboro (historical) | Locale | 348 | Carroll | 42 10 60 N | 094 41 33 W |
| Lanesboro Cemetery | Cemetery | 344 | Carroll | 42 10 52 N | 094 43 24 W |
| Lanesboro Fire Station | Building | 348 | Carroll | 42 11 04 N | 094 41 29 W |
| Lanesboro Post Office | Post Office | 348 | Carroll | 42 11 04 N | 094 41 29 W |
| Lang Eye Clinic | Hospital | 251 | Wapello | 41 01 38 N | 092 23 18 W |
| Lang Hall | Building | 286 | Black Hawk | 42 30 56 N | 092 27 27 W |
| Langan Residence Hall | Building | 311 | Poweshiek | 41 44 59 N | 092 43 19 W |
| Langbehn School (historical) | School | 228 | Clinton | 41 50 40 N | 090 38 11 W |
| Langdon | Populated Place | 417 | Clay | 43 12 57 N | 095 05 17 W |
| Langdon (historical) | Locale | 418 | Clay | 43 12 54 N | 095 05 11 W |
| Langdon Post Office (historical) | Post Office | 417 | Clay | 43 12 57 N | 095 05 17 W |
| Lange Creek | Stream | | O'Brien | 42 57 14 N | 095 42 55 W |
| Langeman's Ford | Park | 304 | Fayette | 42 50 17 N | 091 46 16 W |
| Langes Ferry (historical) | Locale | 192 | Muscatine | 41 34 32 N | 091 05 47 W |
| Langfitt Post Office (historical) | Post Office | 301 | Dallas | 41 41 20 N | 094 09 46 W |
| Langwood 4-H Reserve | Park | 210 | Louisa | 41 16 05 N | 091 09 01 W |
| Langworthy | Populated Place | 262 | Jones | 42 11 28 N | 091 13 27 W |
| Langworthy (historical) | Locale | 262 | Jones | 42 11 28 N | 091 13 27 W |
| Langworthy Cemetery | Cemetery | 282 | Jones | 42 11 16 N | 091 14 18 W |
| Langworthy Post Office (historical) | Post Office | 262 | Jones | 42 11 28 N | 091 13 27 W |
| Lanscaster | Populated Place | 235 | Keokuk | 41 16 32 N | 092 09 54 W |
| Lansing | Locale | 192 | Allamakee | 43 21 25 N | 091 12 43 W |
| Lansing | Populated Place | 206 | Allamakee | 43 21 44 N | 091 12 59 W |
| Lansing Big Lake Public Hunting Area | Park | 189 | Allamakee | 43 24 04 N | 091 13 03 W |
| Lansing City Library | Building | 209 | Allamakee | 43 21 42 N | 091 13 10 W |
| Lansing Clinic | Hospital | 207 | Allamakee | 43 21 44 N | 091 13 07 W |
| Lansing Dental Clinic | Hospital | 200 | Allamakee | 43 21 42 N | 091 12 58 W |
| Lansing Fire Station | Building | 206 | Allamakee | 43 21 44 N | 091 12 59 W |
| Lansing Police Department | Building | 206 | Allamakee | 43 21 44 N | 091 12 59 W |
| Lansing Post Office | Post Office | 205 | Allamakee | 43 21 42 N | 091 13 05 W |
| Lansing Ridge | Ridge | 383 | Allamakee | 43 20 32 N | 091 22 01 W |
| Lansing Ridge Cemetery | Cemetery | 378 | Allamakee | 43 20 44 N | 091 21 24 W |
| Lansing Valley Mobile City | Populated Place | 206 | Allamakee | 43 21 44 N | 091 12 59 W |
| Lansing Wildlife Management Area | Park | 269 | Allamakee | 43 23 50 N | 091 16 12 W |
| Lansrud | Populated Place | 395 | Worth | 43 27 07 N | 093 28 08 W |
| Lansrud Post Office (historical) | Post Office | 395 | Worth | 43 27 07 N | 093 28 08 W |
| Lantern Park Nursing and Rehabilitation Center | Hospital | 213 | Johnson | 41 41 05 N | 091 35 21 W |
| Lantern Park Plaza | Locale | 207 | Johnson | 41 40 55 N | 091 35 36 W |
| Lantz Wildlife Reserve | Park | 241 | Iowa | 41 31 00 N | 091 53 11 W |
| Lanyon | Populated Place | 357 | Webster | 42 13 21 N | 094 11 43 W |
| Lanyon (historical) | Locale | 357 | Webster | 42 13 21 N | 094 11 43 W |
| Lanyon Post Office (historical) | Post Office | 357 | Webster | 42 13 21 N | 094 11 43 W |
| Lao Unity CRC Church | Church | 343 | Woodbury | 42 30 52 N | 096 25 05 W |
| Laporte Post Office (historical) | Post Office | 354 | Clarke | 41 08 57 N | 093 55 51 W |
| Lapworth Creek | Stream | | Pottawattamie | 41 21 39 N | 095 52 41 W |
| Larch Hall | Building | 274 | Story | 42 01 25 N | 093 38 16 W |
| Larch Hill Cemetery | Cemetery | 290 | Tama | 42 15 50 N | 092 27 09 W |
| Larchwood | Populated Place | 450 | Lyon | 43 27 13 N | 096 26 03 W |
| Larchwood (historical) | Locale | 447 | Lyon | 43 27 05 N | 096 26 03 W |
| Larchwood Cemetery | Cemetery | 451 | Lyon | 43 27 41 N | 096 26 45 W |
| Larchwood Chiropractic Clinic | Hospital | 450 | Lyon | 43 27 13 N | 096 26 03 W |
| Larchwood Fire Station | Building | 450 | Lyon | 43 27 13 N | 096 26 03 W |
| Larchwood Medical Clinic | Hospital | 450 | Lyon | 43 27 13 N | 096 26 03 W |
| Larchwood Post Office | Post Office | 450 | Lyon | 43 27 13 N | 096 26 03 W |
| Larchwood Public Library | Building | 450 | Lyon | 43 27 13 N | 096 26 03 W |
| Lard Lake (historical) | Lake | 378 | Sac | 42 32 30 N | 094 59 18 W |
| Lark | Locale | 383 | Worth | 43 18 49 N | 093 28 04 W |
| Lark Post Office (historical) | Post Office | 215 | Allamakee | 43 10 15 N | 091 14 58 W |
| Lark Post Office (historical) | Post Office | 383 | Worth | 43 18 49 N | 093 28 04 W |
| Lark School | School | 319 | Monona | 42 01 52 N | 096 05 19 W |
| Larland | Populated Place | 418 | Audubon | 41 43 54 N | 094 45 47 W |
| Larland Post Office (historical) | Post Office | 418 | Audubon | 41 43 54 N | 094 45 47 W |
| Larrabee | Populated Place | 415 | Cherokee | 42 51 39 N | 095 32 43 W |
| Larrabee (historical) | Locale | 414 | Cherokee | 42 51 47 N | 095 32 44 W |
| Larrabee Post Office | Post Office | 415 | Cherokee | 42 51 39 N | 095 32 43 W |
| Larsen Hall | Building | 286 | Winneshiek | 43 18 37 N | 091 48 19 W |
| Larsen Landing Strip | Airport | 398 | Adair | 41 11 50 N | 094 31 01 W |
| Larson - Tweed Wildlife Area | Park | 381 | Winnebago | 43 26 50 N | 093 32 01 W |
| Larson Lake | Lake | 417 | Cherokee | 42 43 41 N | 095 23 21 W |
| Larson Lake County Park | Park | 417 | Cherokee | 42 43 43 N | 095 23 24 W |
| LaRue Cemetery | Cemetery | 296 | Benton | 42 03 27 N | 092 08 39 W |