Feature Name | Class | Elev. meters | County | Latitude DMS | Longitude DMS |
| Twin Lakes County Park | Park | 259 | Green Lake | 43 47 30 N | 088 58 32 W |
| Twin Lakes Creek | Stream | | Oneida | 45 38 15 N | 089 14 31 W |
| Twin Lakes School (historical) | School | 440 | Sawyer | 46 04 38 N | 091 17 23 W |
| Twin Lakes State Access Point | Locale | 295 | St. Croix | 44 57 54 N | 092 34 32 W |
| Twin Mound Lookout Tower | Tower | 384 | Clark | 44 34 53 N | 090 53 42 W |
| Twin Oaks School (historical) | School | 423 | Marathon | 45 05 25 N | 089 33 12 W |
| Twin Parks 10 D9400 Dam | Dam | 249 | Iowa | 43 05 42 N | 089 55 18 W |
| Twin Parks 12 2WP1782 Dam | Dam | 251 | Iowa | 43 00 42 N | 090 02 36 W |
| Twin Parks 3 2WP1780 Dam | Dam | 253 | Iowa | 43 01 06 N | 090 01 00 W |
| Twin Parks 4 2WP1780 Dam | Dam | 281 | Iowa | 43 01 42 N | 090 02 00 W |
| Twin Parks 6 2WP1780 Dam | Dam | 235 | Iowa | 43 02 36 N | 090 00 06 W |
| Twin Parks 7 Dam | Dam | 296 | Iowa | 43 01 12 N | 089 54 54 W |
| Twin Parks 8 2WP1781 Dam | Dam | 233 | Iowa | 43 03 42 N | 089 57 00 W |
| Twin Parks 9 D9400 Dam | Dam | 254 | Iowa | 43 03 54 N | 089 55 48 W |
| Twin Peaks | Summit | 355 | La Crosse | 44 01 58 N | 090 58 54 W |
| Twin Pine School (historical) | School | 292 | Sauk | 43 32 23 N | 090 03 16 W |
| Twin Platte School | School | 294 | Grant | 42 45 04 N | 090 32 59 W |
| Twin Pond School (historical) | School | 314 | St. Croix | 45 00 46 N | 092 31 04 W |
| Twin Ports Baptist Church | Church | 194 | Douglas | 46 42 32 N | 092 03 12 W |
| Twin River | Stream | | Vilas | 46 00 58 N | 089 12 08 W |
| Twin River School (historical) | School | 248 | Manitowoc | 44 18 45 N | 087 49 36 W |
| Twin Springs Farm | Locale | 295 | Richland | 43 30 30 N | 090 26 57 W |
| Twin Springs Farm | Locale | 317 | Richland | 43 17 45 N | 090 26 51 W |
| Twin Town | Populated Place | 372 | Barron | 45 21 36 N | 092 01 57 W |
| Twin Valley | Valley | | Dunn | 44 42 45 N | 092 03 59 W |
| Twin Valley Lake | Reservoir | 276 | Iowa | 43 01 30 N | 090 05 00 W |
| Twin Valley Lake 6.07 | Reservoir | 275 | Iowa | 43 01 36 N | 090 05 06 W |
| Twin Valley School (historical) | School | 280 | Adams | 43 44 38 N | 089 48 48 W |
| Twin Valley School (historical) | School | 298 | Dunn | 45 02 43 N | 091 45 29 W |
| Twin Willows School | School | 241 | Outagamie | 44 17 42 N | 088 26 48 W |
| Twining Park | Park | 310 | Green | 42 36 29 N | 089 38 38 W |
| Two Axe Lake | Lake | 409 | Sawyer | 45 55 03 N | 091 04 30 W |
| Two Bear Camp | Locale | 388 | Rusk | 45 21 54 N | 091 29 43 W |
| Two Bear Lake | Lake | 360 | Rusk | 45 22 21 N | 091 29 38 W |
| Two Boys Lake | Lake | 401 | Sawyer | 45 54 01 N | 091 12 26 W |
| Two Creek Buried Forest State Natural Area | Park | 44 | Manitowoc | 44 19 34 N | 087 32 41 W |
| Two Creeks | Populated Place | 196 | Manitowoc | 44 18 08 N | 087 33 47 W |
| Two Creeks Air Force Station (historical) | Military (Historical) | | Manitowoc | 44 19 30 N | 087 34 45 W |
| Two Creeks Buried State Forest | Park | 188 | Manitowoc | 44 19 30 N | 087 32 45 W |
| Two Creeks County Park | Park | 180 | Manitowoc | 44 18 19 N | 087 32 43 W |
| Two Creeks Gap Filler Annex (historical) | Military (Historical) | | Manitowoc | 44 19 25 N | 087 34 46 W |
| Two Deer Lake | Lake | 431 | Sawyer | 46 04 51 N | 091 04 38 W |
| Two Island Lake | Lake | 334 | Chippewa | 45 14 09 N | 091 23 44 W |
| Two Island Lake | Lake | 513 | Langlade | 45 26 31 N | 089 25 14 W |
| Two Lakes Campground | Locale | 416 | Bayfield | 46 17 32 N | 091 11 37 W |
| Two Mile Lake | Lake | 317 | Douglas | 46 12 56 N | 091 48 16 W |
| Two Rivers | Populated Place | 184 | Manitowoc | 44 09 14 N | 087 34 09 W |
| Two Rivers Catholic Central School | School | 183 | Manitowoc | 44 08 59 N | 087 34 00 W |
| Two Rivers City Hall | Building | 183 | Manitowoc | 44 08 58 N | 087 34 02 W |
| Two Rivers Municipal Nursing Home | Building | 188 | Manitowoc | 44 09 24 N | 087 33 23 W |
| Two Rivers Post Office | Post Office | 183 | Manitowoc | 44 08 59 N | 087 34 08 W |
| Two Sisters Creek | Stream | | Oneida | 45 47 07 N | 089 32 46 W |
| Two Sisters Lake | Lake | 481 | Oneida | 45 46 16 N | 089 31 30 W |
| Two Sisters Lakes | Lake | 516 | Forest | 45 55 18 N | 088 57 48 W |
| Twomile Creek | Stream | | Wood | 44 21 03 N | 089 50 34 W |
| Twomile School | School | 311 | Wood | 44 21 46 N | 089 49 03 W |
| Tydalen School (historical) | School | 364 | St. Croix | 44 52 33 N | 092 21 10 W |
| Tyler Cemetery | Cemetery | 268 | Manitowoc | 44 02 14 N | 087 58 06 W |
| Tyler Forks | Populated Place | 454 | Iron | 46 20 09 N | 090 31 40 W |
| Tyler Forks | Stream | | Ashland | 46 22 32 N | 090 38 20 W |
| Tyler Lake | Lake | 483 | Oneida | 45 43 33 N | 089 36 50 W |
| Tyler School | School | 258 | Jefferson | 43 04 21 N | 088 50 38 W |
| Tyler School | School | 381 | Marathon | 44 45 22 N | 089 26 51 W |
| Tyler School (historical) | School | 353 | Grant | 43 08 28 N | 090 36 24 W |
| Tyner Lake | Lake | 400 | Sawyer | 45 55 01 N | 091 16 09 W |
| Typner Lake | Lake | 501 | Langlade | 45 18 30 N | 089 12 15 W |
| Tyra Lake | Lake | 446 | Langlade | 45 15 15 N | 088 50 30 W |
| Tyran | Populated Place | 396 | Florence | 45 56 56 N | 088 18 19 W |
| U-Nah-Li-Ya Camp | Locale | 269 | Oconto | 45 06 53 N | 088 26 20 W |
| Ubet | Populated Place | 337 | Polk | 45 21 14 N | 092 31 46 W |
| Ubet School (historical) | School | 341 | Polk | 45 20 46 N | 092 31 49 W |
| Ucil Lake | Lake | 258 | Oconto | 45 04 27 N | 088 15 07 W |
| Ucker Road Cemetery | Cemetery | 275 | Manitowoc | 43 57 58 N | 087 56 33 W |
| Udeys WP73 Dam | Dam | 250 | Columbia | 43 20 12 N | 089 00 36 W |
| Ueeck Lake | Lake | 306 | Waushara | 44 06 48 N | 089 23 49 W |
| Uhrenholdt Memorial State Forest | Forest | 387 | Sawyer | 46 07 05 N | 091 21 27 W |
| Uihlein 3NW81804 Dam | Dam | 420 | Ashland | 46 19 60 N | 090 46 01 W |
| Ukrainian Orthodox Church | Church | 380 | Clark | 45 01 51 N | 090 46 48 W |
| Ula Cemetery | Cemetery | 324 | Green | 42 48 51 N | 089 48 22 W |
| Ulao | Populated Place | 210 | Ozaukee | 43 19 14 N | 087 54 59 W |
| Ulao School | School | 223 | Ozaukee | 43 19 14 N | 087 54 23 W |
| Ullom School | School | 283 | Green | 42 32 58 N | 089 44 26 W |
| Ulvin Hill | Summit | 336 | Pierce | 44 37 50 N | 092 27 18 W |
| Uncle Sam School (historical) | School | 330 | Clark | 44 36 26 N | 090 34 23 W |
| Underhill | Populated Place | 246 | Oconto | 44 52 31 N | 088 23 04 W |
| Underhill Cemetery | Cemetery | 245 | Oconto | 44 52 18 N | 088 23 35 W |
| Underhill School | School | 258 | Outagamie | 44 18 58 N | 088 29 14 W |
| Underwood Creek | Stream | | Waukesha | 43 03 34 N | 088 01 58 W |
| Underwood Elementary School | School | 222 | Milwaukee | 43 02 29 N | 088 03 10 W |
| Underwood Lake | Lake | 254 | Oconto | 45 02 35 N | 088 14 20 W |
| Underwood Memorial Baptist Church | Church | 219 | Milwaukee | 43 03 20 N | 088 00 25 W |
| Underwood Memorial Chapel | Church | 366 | Marathon | 44 56 53 N | 089 38 27 W |
| Underwood State Wildlife Area | Park | 506 | Iron | 46 19 20 N | 090 05 19 W |
| Union | Populated Place | 277 | Eau Claire | 44 50 36 N | 091 32 56 W |
| Union | Populated Place | 334 | Grant | 42 49 49 N | 090 31 34 W |
| Union | Populated Place | 289 | Rock | 42 49 28 N | 089 18 06 W |
| Union Cemetery | Cemetery | 466 | Ashland | 46 01 24 N | 090 29 27 W |
| Union Cemetery | Cemetery | 314 | Burnett | 45 39 02 N | 092 35 53 W |
| Union Cemetery | Cemetery | 247 | Calumet | 43 58 28 N | 088 18 40 W |
| Union Cemetery | Cemetery | 334 | Chippewa | 44 55 41 N | 091 02 04 W |
| Union Cemetery | Cemetery | 293 | Chippewa | 44 58 22 N | 091 12 45 W |
| Union Cemetery | Cemetery | 372 | Dane | 43 00 39 N | 089 43 46 W |
| Union Cemetery | Cemetery | 306 | Dodge | 43 31 34 N | 088 27 05 W |
| Union Cemetery | Cemetery | 310 | Eau Claire | 44 38 60 N | 091 24 25 W |
| Union Cemetery | Cemetery | 326 | Fond du Lac | 43 36 07 N | 088 16 54 W |
| Union Cemetery | Cemetery | 331 | Fond du Lac | 43 43 32 N | 088 10 12 W |
| Union Cemetery | Cemetery | 343 | Grant | 42 57 12 N | 090 57 11 W |
| Union Cemetery | Cemetery | 262 | Jefferson | 42 51 56 N | 088 50 22 W |
| Union Cemetery | Cemetery | 251 | Jefferson | 42 56 03 N | 088 54 31 W |
| Union Cemetery | Cemetery | 280 | Jefferson | 42 57 43 N | 088 53 44 W |