Feature Name | Class | Elev. meters | County | Latitude DMS | Longitude DMS |
| Bladen (historical) | Locale | 376 | Pocahontas | 42 34 38 N | 094 33 41 W |
| Bladensburg | Populated Place | 232 | Wapello | 41 02 46 N | 092 14 14 W |
| Bladensburg Cemetery | Cemetery | 228 | Wapello | 41 02 44 N | 092 16 09 W |
| Bladensburg Christian Church | Church | 232 | Wapello | 41 02 46 N | 092 14 22 W |
| Bladensburg Post Office (historical) | Post Office | 232 | Wapello | 41 02 46 N | 092 14 14 W |
| Blain | Locale | 443 | Buena Vista | 42 33 40 N | 095 18 31 W |
| Blain Cemetery | Cemetery | 264 | Johnson | 41 49 53 N | 091 42 20 W |
| Blaine Post Office (historical) | Post Office | 442 | Buena Vista | 42 34 35 N | 095 18 31 W |
| Blair Cemetery | Cemetery | 338 | Clarke | 40 54 30 N | 093 37 21 W |
| Blair Chapel | Church | 313 | Madison | 41 19 52 N | 093 49 49 W |
| Blair Chapel Cemetery | Cemetery | 316 | Madison | 41 19 53 N | 093 49 46 W |
| Blair Creek | Stream | | Cerro Gordo | 43 14 24 N | 093 12 41 W |
| Blair Meadows Preserve | Park | 346 | Cerro Gordo | 43 09 55 N | 093 15 43 W |
| Blair Post Office (historical) | Post Office | 367 | Pottawattamie | 41 15 36 N | 095 31 35 W |
| Blair Ridge Baptist Church | Church | 249 | Linn | 42 02 30 N | 091 44 01 W |
| Blairsburg | Locale | 375 | Hamilton | 42 28 53 N | 093 38 35 W |
| Blairsburg | Populated Place | 375 | Hamilton | 42 28 48 N | 093 38 35 W |
| Blairsburg Cemetery | Cemetery | 378 | Hamilton | 42 29 33 N | 093 38 45 W |
| Blairsburg Post Office | Post Office | 375 | Hamilton | 42 28 48 N | 093 38 35 W |
| Blairsburg Town Hall | Building | 375 | Hamilton | 42 28 48 N | 093 38 35 W |
| Blairstown | Locale | 256 | Benton | 41 54 34 N | 092 05 03 W |
| Blairstown | Populated Place | 256 | Benton | 41 54 34 N | 092 05 04 W |
| Blairstown City Hall | Building | 256 | Benton | 41 54 15 N | 092 05 02 W |
| Blairstown Fire Station | Building | 258 | Benton | 41 54 32 N | 092 05 03 W |
| Blairstown Post Office | Post Office | 256 | Benton | 41 54 15 N | 092 05 02 W |
| Blairstown Public Library | Building | 259 | Benton | 41 54 32 N | 092 05 05 W |
| Blairstown Schools | School | 258 | Benton | 41 54 25 N | 092 04 56 W |
| Blake Cemetery | Cemetery | 266 | Poweshiek | 41 51 35 N | 092 18 48 W |
| Blake's Grove Chapel | Church | 338 | Franklin | 42 34 41 N | 093 04 46 W |
| Blakesburg | Locale | 275 | Wapello | 40 57 40 N | 092 38 03 W |
| Blakesburg | Populated Place | 276 | Wapello | 40 57 44 N | 092 38 03 W |
| Blakesburg Cemetery | Cemetery | 263 | Monroe | 40 57 47 N | 092 38 25 W |
| Blakesburg Christian Church | Church | 276 | Wapello | 40 57 44 N | 092 38 03 W |
| Blakesburg Methodist Church | Church | 276 | Wapello | 40 57 44 N | 092 38 03 W |
| Blakesburg Post Office | Post Office | 276 | Wapello | 40 57 44 N | 092 38 03 W |
| Blakesburg Public Library | Building | 276 | Wapello | 40 57 44 N | 092 38 03 W |
| Blakesburg Town Hall | Building | 276 | Wapello | 40 57 44 N | 092 38 03 W |
| Blakestad Cemetery | Cemetery | 342 | Mitchell | 43 22 16 N | 092 56 25 W |
| Blakeway Cemetery | Cemetery | 215 | Des Moines | 40 48 45 N | 091 21 07 W |
| Blanchaine Cemetery | Cemetery | 283 | Clayton | 42 45 60 N | 091 20 30 W |
| Blanchard | Populated Place | 309 | Page | 40 34 45 N | 095 13 18 W |
| Blanchard (historical) | Locale | 299 | Page | 40 34 48 N | 095 13 29 W |
| Blanchard Cemetery | Cemetery | 284 | Fremont | 40 44 08 N | 095 51 06 W |
| Blanchard Cemetery | Cemetery | 326 | Page | 40 34 48 N | 095 12 12 W |
| Blanchard Cemetery | Cemetery | 332 | Webster | 42 24 08 N | 093 59 60 W |
| Blanchard Elevator | Locale | 309 | Page | 40 34 45 N | 095 13 18 W |
| Blanchard Post Office | Post Office | 309 | Page | 40 34 45 N | 095 13 18 W |
| Blanchard United Methodist Church | Church | 309 | Page | 40 34 45 N | 095 13 18 W |
| Blanden | Populated Place | 376 | Pocahontas | 42 34 38 N | 094 33 41 W |
| Blanden Memorial Art Museum | Building | 334 | Webster | 42 30 10 N | 094 11 07 W |
| Blanden Memorial Art Museum Library | Building | 334 | Webster | 42 30 10 N | 094 11 07 W |
| Blanden Post Office (historical) | Post Office | 376 | Pocahontas | 42 34 38 N | 094 33 41 W |
| Blank Children's Hospital | Hospital | 266 | Polk | 41 35 21 N | 093 37 59 W |
| Blank Golf Course | Locale | 276 | Polk | 41 31 00 N | 093 37 26 W |
| Blank Park | Park | 291 | Polk | 41 30 58 N | 093 37 04 W |
| Blank Park Zoo | Locale | 273 | Polk | 41 31 07 N | 093 37 30 W |
| Blank Performing Arts Center | Building | 289 | Warren | 41 21 55 N | 093 34 02 W |
| Blank Ridge | Ridge | 315 | Boone | 41 56 57 N | 093 54 12 W |
| Blarney Stone Park | Park | 273 | Monroe | 40 58 34 N | 093 03 02 W |
| Blazing Star Prairie | Area | 352 | Cerro Gordo | 43 01 15 N | 093 11 14 W |
| Blazing Star Prairie Area | Park | 285 | Buchanan | 42 21 22 N | 091 48 11 W |
| Blenco Post Office (historical) | Post Office | 317 | Monona | 41 56 13 N | 096 05 26 W |
| Blencoe | Locale | 317 | Monona | 41 55 50 N | 096 04 55 W |
| Blencoe | Populated Place | 317 | Monona | 41 55 49 N | 096 04 51 W |
| Blencoe Community Center | Building | 317 | Monona | 41 55 50 N | 096 04 51 W |
| Blencoe Post Office | Post Office | 317 | Monona | 41 55 50 N | 096 04 50 W |
| Blessed Sacrament Church | Church | 275 | Black Hawk | 42 30 15 N | 092 23 08 W |
| Blessed Sacrament Church | Church | 393 | Woodbury | 42 31 21 N | 096 24 05 W |
| Blessed Sacrament School | School | 274 | Black Hawk | 42 30 15 N | 092 23 07 W |
| Blessed Sacrament School | School | 390 | Woodbury | 42 31 24 N | 096 24 05 W |
| Blessing | Populated Place | 304 | Black Hawk | 42 18 42 N | 092 27 22 W |
| Blessing Cemetery | Cemetery | 304 | Black Hawk | 42 18 41 N | 092 27 28 W |
| Blessing Post Office (historical) | Post Office | 304 | Black Hawk | 42 18 42 N | 092 27 22 W |
| Bleubaugh Creek | Stream | | Monroe | 40 58 15 N | 093 04 01 W |
| Bliar Creek Area | Park | 358 | Worth | 43 16 13 N | 093 10 51 W |
| Bliedorn | Populated Place | 236 | Clinton | 41 54 09 N | 090 40 42 W |
| Bliedorn Post Office (historical) | Post Office | 236 | Clinton | 41 54 09 N | 090 40 42 W |
| Bliesman Landing | Locale | 359 | Crawford | 42 07 10 N | 095 17 39 W |
| Blinkman Chiropractic Center | Hospital | 377 | Cerro Gordo | 43 07 60 N | 093 22 32 W |
| Bliss Cancer Center | Hospital | 284 | Story | 42 01 57 N | 093 36 42 W |
| Blockhouse Site | Park | 314 | Pottawattamie | 41 15 52 N | 095 50 28 W |
| Blockly | Populated Place | 306 | Decatur | 40 39 35 N | 093 45 18 W |
| Blockly (historical) | Locale | 306 | Decatur | 40 39 35 N | 093 45 18 W |
| Blockly Post Office (historical) | Post Office | 306 | Decatur | 40 39 35 N | 093 45 18 W |
| Blockton | Populated Place | 341 | Taylor | 40 36 56 N | 094 28 38 W |
| Blockton (historical) | Locale | 329 | Taylor | 40 37 02 N | 094 28 51 W |
| Blockton Baptist Church | Church | 341 | Taylor | 40 36 56 N | 094 28 38 W |
| Blockton Christian Church | Church | 341 | Taylor | 40 36 56 N | 094 28 38 W |
| Blockton City Hall | Building | 341 | Taylor | 40 36 56 N | 094 28 38 W |
| Blockton Post Office | Post Office | 341 | Taylor | 40 36 56 N | 094 28 38 W |
| Blodgett Cemetery | Cemetery | 286 | Linn | 42 12 45 N | 091 34 40 W |
| Blong Chiropractic Clinic | Hospital | 315 | Lucas | 41 00 56 N | 093 18 29 W |
| Blood Run | Stream | | Lyon | 43 27 53 N | 096 35 07 W |
| Blood Run / Rock Island National Landmark | Park | 411 | Lyon | 43 28 55 N | 096 34 11 W |
| Bloody Run | Stream | | Clayton | 43 02 30 N | 091 10 39 W |
| Bloody Run | Stream | | Delaware | 42 38 49 N | 091 08 40 W |
| Bloody Run | Stream | | Dubuque | 42 33 45 N | 090 42 31 W |
| Bloody Run | Stream | | Floyd | 43 01 43 N | 092 38 05 W |
| Bloody Run | Stream | | Humboldt | 42 49 53 N | 094 10 03 W |
| Bloody Run County Park | Park | 203 | Clayton | 43 02 20 N | 091 12 50 W |
| Bloody Run School | School | 274 | Dubuque | 42 37 22 N | 090 45 27 W |
| Bloody Run Wildlife Management Area | Park | 226 | Clayton | 43 02 10 N | 091 14 20 W |
| Bloomer School | School | 302 | Pottawattamie | 41 15 31 N | 095 51 18 W |
| Bloomfield | Populated Place | 266 | Davis | 40 45 06 N | 092 24 54 W |
| Bloomfield (historical) | Locale | 262 | Davis | 40 44 58 N | 092 25 31 W |
| Bloomfield Agri-Center Elevator | Locale | 263 | Davis | 40 44 50 N | 092 25 33 W |
| Bloomfield Care Center | Hospital | 266 | Davis | 40 45 36 N | 092 25 05 W |
| Bloomfield Cemetery | Cemetery | 255 | Clinton | 41 56 45 N | 090 37 10 W |
| Bloomfield Cemetery | Cemetery | 254 | Mahaska | 41 15 53 N | 092 33 56 W |
| Bloomfield Cemetery | Cemetery | 381 | Winneshiek | 43 06 55 N | 091 41 24 W |