Feature Name | Class | Elev. meters | County | Latitude DMS | Longitude DMS |
| Irish Ridge | Ridge | 377 | Vernon | 43 36 08 N | 090 59 35 W |
| Irish Ridge School (historical) | School | 372 | Crawford | 43 03 48 N | 091 03 42 W |
| Irish Valley | Valley | | Buffalo | 44 17 51 N | 091 40 48 W |
| Irish Valley | Valley | | Monroe | 44 10 58 N | 090 47 48 W |
| Irish Valley | Valley | | Sauk | 43 18 53 N | 089 57 43 W |
| Irish Valley School (historical) | School | 236 | Buffalo | 44 17 52 N | 091 40 49 W |
| Irlbeck Airport | Airport | 302 | St. Croix | 45 05 44 N | 092 40 26 W |
| Irma | Populated Place | 466 | Lincoln | 45 21 05 N | 089 39 59 W |
| Irma Hill | Summit | 536 | Lincoln | 45 21 07 N | 089 39 15 W |
| Irogami Lake | Lake | 264 | Waushara | 44 03 56 N | 089 13 57 W |
| Iron Belt | Populated Place | 474 | Iron | 46 24 02 N | 090 19 28 W |
| Iron County | Civil | 524 | Iron | 46 15 02 N | 090 14 01 W |
| Iron County Courthouse | Building | 467 | Iron | 46 26 53 N | 090 10 60 W |
| Iron County Fairground | Park | 352 | Iron | 46 29 24 N | 090 24 41 W |
| Iron County Jail | Building | 452 | Iron | 46 27 19 N | 090 11 02 W |
| Iron County Memorial Building | Building | 465 | Iron | 46 26 53 N | 090 10 57 W |
| Iron Creek | Stream | | Buffalo | 44 21 30 N | 091 55 56 W |
| Iron Creek | Stream | | Burnett | 45 55 30 N | 092 38 26 W |
| Iron Creek | Stream | | Chippewa | 44 59 45 N | 091 14 39 W |
| Iron Creek | Stream | | Dunn | 44 49 46 N | 091 45 36 W |
| Iron Creek | Stream | 350 | Marathon | 44 46 52 N | 089 44 36 W |
| Iron Creek Cemetery | Cemetery | 264 | Dunn | 44 51 10 N | 091 46 44 W |
| Iron Creek School (historical) | School | 215 | Buffalo | 44 21 43 N | 091 55 43 W |
| Iron Creek School (historical) | School | 275 | Dunn | 44 51 49 N | 091 46 41 W |
| Iron Lake | Lake | 336 | Bayfield | 46 32 02 N | 091 26 29 W |
| Iron Mound | Summit | 294 | Jackson | 44 17 32 N | 090 43 24 W |
| Iron Ridge | Populated Place | 285 | Dodge | 43 23 59 N | 088 31 57 W |
| Iron River | Populated Place | 339 | Bayfield | 46 33 52 N | 091 24 30 W |
| Iron River | Stream | | Ashland | 46 16 12 N | 090 42 25 W |
| Iron River | Stream | | Bayfield | 46 45 60 N | 091 29 16 W |
| Iron River Flowage 8.37 | Reservoir | 319 | Bayfield | 46 33 60 N | 091 25 25 W |
| Iron River Light and Power Company WP182 Dam | Dam | 319 | Bayfield | 46 33 60 N | 091 25 25 W |
| Iron River Lookout Tower | Tower | 386 | Bayfield | 46 34 35 N | 091 19 26 W |
| Iron River National Fish Hatchery | Locale | 284 | Bayfield | 46 38 57 N | 091 21 12 W |
| Iron Run | Stream | | Clark | 44 43 07 N | 090 54 30 W |
| Iron Run Flowage | Lake | 306 | Clark | 44 42 36 N | 090 52 60 W |
| Iron Springs Creek | Stream | | Marinette | 45 07 57 N | 088 05 39 W |
| Ironton | Populated Place | 291 | Sauk | 43 32 46 N | 090 08 28 W |
| Ironton-La Valle Elementary School | School | 276 | Sauk | 43 34 41 N | 090 08 07 W |
| Ironwood Island | Island | 209 | Ashland | 47 00 01 N | 090 36 56 W |
| Irvin Coulee | Valley | | Trempealeau | 44 21 58 N | 091 18 53 W |
| Irvin Coulee School (historical) | School | 272 | Trempealeau | 44 19 50 N | 091 20 19 W |
| Irvin Creek | Stream | | Trempealeau | 44 22 14 N | 091 18 50 W |
| Irvin Young Memorial Library | Building | 254 | Walworth | 42 49 59 N | 088 44 12 W |
| Irvine | Populated Place | 250 | Chippewa | 44 55 32 N | 091 25 12 W |
| Irvine Park | Park | 280 | Chippewa | 44 57 09 N | 091 24 04 W |
| Irving | Populated Place | 228 | Jackson | 44 11 24 N | 090 54 05 W |
| Irving Cemetery | Cemetery | 247 | Jackson | 44 10 50 N | 090 54 42 W |
| Irving Creek | Stream | | Dunn | 44 50 08 N | 091 57 13 W |
| Irving Creek Cemetery | Cemetery | 285 | Dunn | 44 51 05 N | 092 00 23 W |
| Irving Elementary School | School | 233 | Milwaukee | 43 00 15 N | 088 02 26 W |
| Irving Lake | Lake | 515 | Vilas | 46 03 43 N | 089 28 30 W |
| Irving School | School | 231 | Jackson | 44 11 14 N | 090 54 07 W |
| Irving School | School | 364 | Marathon | 44 57 09 N | 089 38 19 W |
| Irving School | School | 314 | Wood | 44 23 44 N | 089 48 49 W |
| Irving School (historical) | School | 364 | Barron | 45 18 29 N | 091 47 32 W |
| Irvington | Populated Place | 234 | Dunn | 44 50 10 N | 091 57 17 W |
| Irwin School | School | 185 | Brown | 44 27 06 N | 088 03 22 W |
| Isaac Lake | Lake | 290 | Burnett | 45 43 10 N | 092 38 13 W |
| Isaar | Populated Place | 253 | Outagamie | 44 34 18 N | 088 17 04 W |
| Isabelle Creek | Stream | | Pierce | 44 34 46 N | 092 26 15 W |
| Isham Valley | Valley | | Buffalo | 44 33 23 N | 091 50 24 W |
| Isherwood Lateral | Canal | 327 | Portage | 44 23 46 N | 089 30 08 W |
| Islamic Center and Mosque | Church | 274 | Eau Claire | 44 48 14 N | 091 26 10 W |
| Island Beach | Populated Place | 230 | Winnebago | 44 05 28 N | 088 30 10 W |
| Island Cemetery | Cemetery | 257 | Jefferson | 43 10 21 N | 088 55 15 W |
| Island Creek | Stream | | Iron | 46 01 32 N | 090 11 05 W |
| Island Creek | Stream | | Sawyer | 45 51 13 N | 090 57 49 W |
| Island Creek | Stream | | Shawano | 44 53 51 N | 088 47 26 W |
| Island Lake | Lake | 354 | Bayfield | 46 23 12 N | 091 31 47 W |
| Island Lake | Lake | 335 | Bayfield | 46 32 18 N | 091 18 21 W |
| Island Lake | Lake | 296 | Burnett | 46 01 43 N | 092 16 23 W |
| Island Lake | Lake | 274 | Dane | 42 55 36 N | 089 17 37 W |
| Island Lake | Lake | 326 | Douglas | 46 21 16 N | 091 46 09 W |
| Island Lake | Lake | 482 | Iron | 46 02 13 N | 090 10 56 W |
| Island Lake | Lake | 513 | Iron | 46 15 51 N | 090 18 07 W |
| Island Lake | Lake | 267 | Marinette | 45 15 05 N | 088 13 42 W |
| Island Lake | Lake | 230 | Marinette | 45 25 27 N | 087 56 33 W |
| Island Lake | Lake | 483 | Oneida | 45 44 46 N | 089 37 05 W |
| Island Lake | Lake | 495 | Oneida | 45 49 44 N | 089 07 59 W |
| Island Lake | Lake | 315 | Polk | 45 13 50 N | 092 23 46 W |
| Island Lake | Lake | 287 | Polk | 45 17 37 N | 092 36 45 W |
| Island Lake | Lake | 477 | Price | 45 57 09 N | 090 12 52 W |
| Island Lake | Lake | 397 | Sawyer | 45 57 06 N | 091 26 47 W |
| Island Lake | Lake | 415 | Sawyer | 45 53 30 N | 090 57 01 W |
| Island Lake | Lake | 296 | Shawano | 44 55 08 N | 088 46 21 W |
| Island Lake | Lake | 488 | Vilas | 46 06 59 N | 089 47 34 W |
| Island Lake | Lake | 309 | Washburn | 45 57 27 N | 091 56 30 W |
| Island Lake | Populated Place | 330 | Rusk | 45 19 08 N | 091 22 09 W |
| Island Lake | Reservoir | 326 | Rusk | 45 19 15 N | 091 22 14 W |
| Island Lake Cemetery | Cemetery | 329 | Rusk | 45 19 42 N | 091 21 48 W |
| Island Lake Church | Church | 329 | Rusk | 45 19 40 N | 091 21 50 W |
| Island Lake Fire Tower (historical) | Tower | 530 | Iron | 46 16 21 N | 090 16 45 W |
| Island Lake WP363 Dam | Dam | 326 | Rusk | 45 19 12 N | 091 22 13 W |
| Island Number Fifty-four | Island | 199 | Buffalo | 44 09 07 N | 091 46 55 W |
| Island Number Fifty-three | Island | 199 | Buffalo | 44 09 20 N | 091 47 32 W |
| Island Number Fifty-two | Island | 200 | Buffalo | 44 09 23 N | 091 47 45 W |
| Island Number Ninety-one | Island | 195 | La Crosse | 43 55 38 N | 091 21 30 W |
| Island Number One | Island | 492 | Vilas | 45 55 35 N | 089 25 54 W |
| Island Number One Hundred Eighty-one | Island | 187 | Grant | 42 54 45 N | 091 08 34 W |
| Island Number One Hundred Fifty-nine | Island | 189 | Crawford | 43 13 29 N | 091 04 59 W |
| Island Number One Hundred Fifty-One (historical) | Island | 189 | Crawford | 43 17 36 N | 091 04 17 W |
| Island Number One Hundred Fifty-Six | Island | 194 | Crawford | 43 15 49 N | 091 03 25 W |
| Island Number One Hundred Forty-six | Island | 189 | Vernon | 43 21 26 N | 091 12 06 W |
| Island Number One Hundred Forty-three | Island | 189 | Vernon | 43 22 01 N | 091 11 24 W |
| Island Number One Hundred Ninety-two | Island | 185 | Grant | 42 43 36 N | 091 01 33 W |
| Island Number One Hundred Seventy | Island | 188 | Crawford | 43 04 03 N | 091 10 44 W |
| Island Number One Hundred Seventy-seven | Island | 187 | Grant | 42 56 10 N | 091 08 42 W |
| Island Number One Hundred Seventy-two | Island | 188 | Crawford | 43 02 32 N | 091 10 04 W |
| Island Number One Hundred Sixty-seven | Island | 187 | Crawford | 43 05 27 N | 091 10 28 W |