Feature Name | Class | Elev. meters | County | Latitude DMS | Longitude DMS |
| Union Gospel Mission | Church | 128 | Williamson | 37 48 25 N | 089 02 37 W |
| Union Grove | Populated Place | 210 | Whiteside | 41 50 03 N | 090 01 35 W |
| Union Grove Cemetery | Cemetery | 166 | Bond | 38 57 17 N | 089 25 48 W |
| Union Grove Cemetery | Cemetery | 172 | Marion | 38 33 46 N | 088 51 32 W |
| Union Grove Cemetery | Cemetery | 213 | Putnam | 41 14 29 N | 089 15 53 W |
| Union Grove Cemetery | Cemetery | 207 | Whiteside | 41 49 34 N | 089 59 52 W |
| Union Grove Church | Church | 122 | Saline | 37 48 16 N | 088 30 10 W |
| Union Grove Church | Church | 159 | Williamson | 37 47 10 N | 088 50 10 W |
| Union Grove Church | Church | 119 | Williamson | 37 50 07 N | 088 39 07 W |
| Union Grove Church (historical) | Church | 212 | Knox | 40 52 16 N | 090 08 11 W |
| Union Grove Church (historical) | Church | 181 | Morgan | 39 31 12 N | 090 10 27 W |
| Union Grove Missionary Baptist Church | Church | 184 | Cook | 41 51 39 N | 087 43 45 W |
| Union Grove School | School | 158 | Madison | 38 49 08 N | 089 51 52 W |
| Union Grove School (historical) | School | 168 | Bond | 38 57 18 N | 089 25 44 W |
| Union Grove School (historical) | School | 177 | Cass | 39 53 00 N | 090 19 42 W |
| Union Grove School (historical) | School | 172 | Greene | 39 30 22 N | 090 10 05 W |
| Union Grove School (historical) | School | 137 | Jefferson | 38 14 05 N | 088 43 19 W |
| Union Grove School (historical) | School | 157 | Madison | 38 49 07 N | 089 51 50 W |
| Union Grove School (historical) | School | 186 | Morgan | 39 49 01 N | 090 08 45 W |
| Union Grove School (historical) | School | 200 | Schuyler | 40 16 14 N | 090 36 08 W |
| Union Grove School (historical) | School | 159 | Williamson | 37 47 24 N | 088 50 10 W |
| Union Grove Youth Camp | Locale | 146 | Wayne | 38 28 24 N | 088 34 07 W |
| Union High School | School | 215 | Henderson | 40 50 59 N | 090 54 04 W |
| Union Hill | Populated Place | 188 | Kankakee | 41 06 27 N | 088 08 48 W |
| Union Hill | Populated Place | 177 | St. Clair | 38 35 17 N | 090 00 21 W |
| Union Hill Cemetery | Cemetery | 147 | Hamilton | 38 05 47 N | 088 34 15 W |
| Union Hill Cemetery | Cemetery | 174 | St. Clair | 38 28 00 N | 090 04 05 W |
| Union Hill Missionary Baptist Church | Church | 184 | Cook | 41 51 52 N | 087 43 42 W |
| Union Hill School (historical) | School | 180 | St. Clair | 38 35 00 N | 090 00 42 W |
| Union Hills Cemetery | Cemetery | 169 | Jackson | 37 40 31 N | 089 15 38 W |
| Union League Club | Building | 181 | Cook | 41 52 40 N | 087 37 48 W |
| Union Miners Cemetery | Cemetery | 207 | Macoupin | 39 04 50 N | 089 43 57 W |
| Union Mission | Church | 144 | Tazewell | 40 34 15 N | 089 39 03 W |
| Union Missionary Baptist Church | Church | 184 | Cook | 41 53 32 N | 087 42 41 W |
| Union Missionary Baptist Church | Church | 179 | Cook | 41 53 58 N | 087 38 15 W |
| Union Missionary Baptist Church | Church | 239 | McLean | 40 28 33 N | 088 59 51 W |
| Union Park | Park | 182 | Cook | 41 53 02 N | 087 39 53 W |
| Union Park | Park | 190 | Sangamon | 39 35 27 N | 089 44 31 W |
| Union Park | Park | 225 | Vermilion | 40 28 32 N | 087 39 45 W |
| Union Point | Populated Place | 110 | Union | 37 32 57 N | 089 30 14 W |
| Union Point School | School | 191 | Union | 37 35 17 N | 089 16 58 W |
| Union Prairie Church | Church | 207 | Moultrie | 39 39 59 N | 088 28 36 W |
| Union Prather Cemetery | Cemetery | 156 | Greene | 39 26 20 N | 090 15 02 W |
| Union Ridge Bible Church | Church | 194 | Cook | 41 57 39 N | 087 47 49 W |
| Union Ridge Cemetery | Cemetery | 195 | Cook | 41 58 49 N | 087 47 44 W |
| Union Ridge Cemetery | Cemetery | 137 | White | 37 55 44 N | 088 10 18 W |
| Union Ridge Church | Church | 138 | White | 37 55 46 N | 088 10 16 W |
| Union Ridge Elementary School | School | 195 | Cook | 41 57 54 N | 087 47 56 W |
| Union School | School | 209 | Macon | 39 50 06 N | 089 02 55 W |
| Union School | School | 190 | Montgomery | 39 20 54 N | 089 29 37 W |
| Union School (historical) | School | 197 | Adams | 39 55 10 N | 091 16 29 W |
| Union School (historical) | School | 205 | Adams | 39 45 26 N | 091 11 46 W |
| Union School (historical) | School | 185 | Adams | 40 02 17 N | 091 22 07 W |
| Union School (historical) | School | 218 | Adams | 40 04 42 N | 091 00 40 W |
| Union School (historical) | School | 221 | Adams | 40 06 22 N | 090 59 25 W |
| Union School (historical) | School | 202 | Adams | 40 08 13 N | 091 09 57 W |
| Union School (historical) | School | 167 | Bond | 38 52 11 N | 089 18 40 W |
| Union School (historical) | School | 213 | Bureau | 41 19 16 N | 089 35 51 W |
| Union School (historical) | School | 143 | Calhoun | 39 03 18 N | 090 36 35 W |
| Union School (historical) | School | 262 | Carroll | 42 04 50 N | 089 52 28 W |
| Union School (historical) | School | 176 | Cass | 39 52 29 N | 090 16 33 W |
| Union School (historical) | School | 195 | Cass | 39 58 57 N | 090 16 05 W |
| Union School (historical) | School | 207 | Champaign | 40 09 23 N | 087 59 41 W |
| Union School (historical) | School | 153 | Clark | 39 26 54 N | 087 33 14 W |
| Union School (historical) | School | 139 | Clinton | 38 31 34 N | 089 16 59 W |
| Union School (historical) | School | 195 | Coles | 39 22 51 N | 088 27 43 W |
| Union School (historical) | School | 186 | Crawford | 38 54 55 N | 087 42 47 W |
| Union School (historical) | School | 182 | Cumberland | 39 18 10 N | 088 16 01 W |
| Union School (historical) | School | 160 | Fayette | 39 00 19 N | 089 01 29 W |
| Union School (historical) | School | 161 | Fayette | 39 07 43 N | 089 00 14 W |
| Union School (historical) | School | 128 | Franklin | 37 51 55 N | 089 00 24 W |
| Union School (historical) | School | 192 | Greene | 39 18 16 N | 090 21 24 W |
| Union School (historical) | School | 149 | Hamilton | 38 06 38 N | 088 40 33 W |
| Union School (historical) | School | 176 | Hancock | 40 22 13 N | 090 57 26 W |
| Union School (historical) | School | 204 | Hancock | 40 19 39 N | 091 09 43 W |
| Union School (historical) | School | 143 | Hardin | 37 26 35 N | 088 24 19 W |
| Union School (historical) | School | 214 | Henry | 41 19 21 N | 089 58 17 W |
| Union School (historical) | School | 201 | Jackson | 37 51 54 N | 089 25 54 W |
| Union School (historical) | School | 166 | Jasper | 38 57 05 N | 088 18 56 W |
| Union School (historical) | School | 189 | Jersey | 39 03 53 N | 090 19 39 W |
| Union School (historical) | School | 282 | Jo Daviess | 42 23 11 N | 090 06 28 W |
| Union School (historical) | School | 272 | Jo Daviess | 42 13 08 N | 089 57 17 W |
| Union School (historical) | School | 237 | Kane | 42 04 07 N | 088 17 30 W |
| Union School (historical) | School | 201 | Kendall | 41 35 29 N | 088 21 44 W |
| Union School (historical) | School | 235 | Knox | 41 08 13 N | 090 22 49 W |
| Union School (historical) | School | 187 | Knox | 40 48 55 N | 090 04 51 W |
| Union School (historical) | School | 235 | Knox | 40 54 36 N | 090 20 10 W |
| Union School (historical) | School | 230 | Knox | 41 03 16 N | 090 02 36 W |
| Union School (historical) | School | 198 | La Salle | 41 32 38 N | 088 44 52 W |
| Union School (historical) | School | 199 | La Salle | 41 10 42 N | 088 45 34 W |
| Union School (historical) | School | 146 | Lawrence | 38 47 55 N | 087 53 20 W |
| Union School (historical) | School | 149 | Lawrence | 38 50 11 N | 087 34 35 W |
| Union School (historical) | School | 128 | Lawrence | 38 44 30 N | 087 35 37 W |
| Union School (historical) | School | 153 | Lawrence | 38 39 28 N | 087 46 10 W |
| Union School (historical) | School | 263 | Lee | 41 53 19 N | 089 12 25 W |
| Union School (historical) | School | 183 | Macoupin | 39 15 41 N | 090 01 39 W |
| Union School (historical) | School | 159 | Madison | 38 42 22 N | 089 42 26 W |
| Union School (historical) | School | 171 | Madison | 38 56 13 N | 090 09 28 W |
| Union School (historical) | School | 150 | Marion | 38 31 09 N | 088 44 58 W |
| Union School (historical) | School | 172 | Marion | 38 39 50 N | 088 54 46 W |
| Union School (historical) | School | 150 | Marshall | 41 06 41 N | 089 24 29 W |
| Union School (historical) | School | 150 | Mason | 40 24 22 N | 089 45 49 W |
| Union School (historical) | School | 145 | Mason | 40 09 20 N | 090 08 23 W |
| Union School (historical) | School | 151 | Mason | 40 20 45 N | 089 49 46 W |
| Union School (historical) | School | 124 | Massac | 37 16 07 N | 088 54 29 W |
| Union School (historical) | School | 204 | McDonough | 40 24 41 N | 090 34 47 W |
| Union School (historical) | School | 170 | McDonough | 40 21 26 N | 090 53 01 W |
| Union School (historical) | School | 235 | McLean | 40 33 36 N | 088 47 02 W |
| Union School (historical) | School | 229 | McLean | 40 38 06 N | 088 57 53 W |
| Union School (historical) | School | 177 | Menard | 40 05 29 N | 089 37 26 W |