Feature Name | Class | Elev. meters | County | Latitude DMS | Longitude DMS |
| Jinks Hollow | Valley | | Henderson | 40 55 27 N | 090 54 25 W |
| Jirka School | School | 184 | Cook | 41 51 33 N | 087 39 43 W |
| Jirtle Park | Park | 210 | Cook | 41 29 32 N | 087 37 54 W |
| Jniper Park | Park | 183 | Cook | 41 56 55 N | 087 40 00 W |
| Jo Daviess County | Civil | 226 | Jo Daviess | 42 21 00 N | 090 11 00 W |
| Jo Daviess County Courthouse | Building | 194 | Jo Daviess | 42 25 06 N | 090 25 32 W |
| Joan Graves Edwards Heliport | Airport | 190 | Union | 37 27 50 N | 089 14 45 W |
| Joanna Park | Park | 211 | Lake | 42 27 31 N | 087 51 07 W |
| Job Training Institute | School | 192 | Cook | 41 54 57 N | 087 50 34 W |
| Jobbers Park | Park | 181 | Kankakee | 41 06 44 N | 087 52 15 W |
| Jobs Creek | Stream | | Cass | 40 03 03 N | 090 13 34 W |
| Jobst Hall | Building | 183 | Peoria | 40 41 59 N | 089 37 01 W |
| Jockisch Methodist Cemetery | Cemetery | 172 | Cass | 39 57 02 N | 090 20 18 W |
| Joe Branch | Stream | | Marion | 38 30 54 N | 088 47 02 W |
| Joe Duncan School (historical) | School | 211 | Hancock | 40 28 08 N | 090 55 50 W |
| Joe Louis 'The Champ' Golf Course | Locale | 182 | Cook | 41 39 14 N | 087 38 40 W |
| Joe Louis Golf Course | Locale | 182 | Cook | 41 39 18 N | 087 38 41 W |
| Joe Orr Woods | Woods | 193 | Cook | 41 31 11 N | 087 37 43 W |
| Joel Hall Cemetery | Cemetery | 184 | Menard | 39 57 18 N | 089 43 36 W |
| Joel T Headley Public School (historical) | School | 180 | Cook | 41 55 12 N | 087 39 33 W |
| Joes Creek | Stream | | Greene | 39 16 51 N | 090 09 08 W |
| Joes Fork | Stream | | Clark | 39 15 57 N | 087 41 58 W |
| Joes Pond | Lake | 203 | Cook | 41 42 09 N | 087 52 35 W |
| Joes Slough | Swamp | 107 | Gallatin | 37 50 16 N | 088 09 30 W |
| Joetta | Populated Place | 204 | Hancock | 40 26 01 N | 090 55 53 W |
| Joey Eaton Grave | Cemetery | 177 | Schuyler | 40 11 52 N | 090 48 12 W |
| Johanna Church (historical) | Church | 196 | Monroe | 38 19 58 N | 090 14 07 W |
| Johannisburg | Populated Place | 134 | Washington | 38 23 04 N | 089 39 11 W |
| Johannisburg Grade School | School | 139 | Washington | 38 21 00 N | 089 38 57 W |
| Johannot (historical) | Locale | 205 | Vermilion | 40 21 32 N | 087 35 16 W |
| John A Bannes Elementary School | School | 214 | Cook | 41 35 04 N | 087 47 48 W |
| John A Graham Correctional Center | Building | 193 | Montgomery | 39 07 40 N | 089 28 24 W |
| John A Logan College | School | 125 | Williamson | 37 44 52 N | 089 05 20 W |
| John A Murphy Memorial Auditorium | Building | 179 | Cook | 41 53 39 N | 087 37 34 W |
| John Adams Elementary School | School | 206 | Macon | 39 48 58 N | 088 57 28 W |
| John Amico School of Hair Design | School | 189 | Cook | 41 45 15 N | 087 44 28 W |
| John Blumberg Park | Park | 203 | Lake | 42 10 55 N | 087 50 53 W |
| John C Roe Park | Park | 222 | Lee | 41 51 26 N | 089 28 33 W |
| John Campbell Cemetery | Cemetery | 186 | Sangamon | 39 40 10 N | 089 47 58 W |
| John Crerar Library | Building | 180 | Cook | 41 47 26 N | 087 36 11 W |
| John D Rennick Airport | Airport | 136 | Woodford | 40 52 02 N | 089 27 11 W |
| John Dean School (historical) | School | 199 | Fulton | 40 33 45 N | 090 02 16 W |
| John Deere Middle School | School | 209 | Rock Island | 41 29 28 N | 090 31 20 W |
| John Dixon Park | Park | 206 | Lee | 41 51 02 N | 089 29 10 W |
| John Dunham Spring | Spring | 151 | Jersey | 39 09 55 N | 090 27 35 W |
| John E Albright Middle School | School | 207 | DuPage | 41 52 09 N | 087 58 08 W |
| John E Egan Water Reclamation Plant | Locale | 217 | Cook | 42 01 05 N | 088 02 20 W |
| John E Hufmeyer Building | Building | 182 | Cook | 41 55 55 N | 087 39 31 W |
| John Eaton Quarry | Mine | 237 | Winnebago | 42 18 45 N | 089 20 10 W |
| John Epler Taylor Cemetery | Cemetery | 183 | Cass | 39 52 45 N | 090 10 22 W |
| John F Kennedy Elementary School | School | 187 | Bureau | 41 19 57 N | 089 12 25 W |
| John F Kennedy Elementary School | School | 197 | Cook | 41 57 00 N | 087 52 39 W |
| John F Kennedy Park | Park | 196 | Lake | 42 09 32 N | 087 47 18 W |
| John Fewkes Tower | Building | 179 | Cook | 41 53 51 N | 087 37 48 W |
| John Foster Dulles School | School | 188 | Cook | 41 44 43 N | 087 46 03 W |
| John Gates Elementary School | School | 201 | Kane | 41 44 31 N | 088 18 00 W |
| John Goin Lake | Reservoir | 137 | Hamilton | 38 06 24 N | 088 34 48 W |
| John Goin Lake Dam | Dam | 137 | Hamilton | 38 06 24 N | 088 34 48 W |
| John Greer Elementary School | School | 216 | Vermilion | 40 28 00 N | 087 40 46 W |
| John H Garrelts Airport | Airport | 228 | Ford | 40 39 05 N | 088 11 05 W |
| John Hancock School | School | 189 | Cook | 41 45 01 N | 087 43 51 W |
| John Hancock Tower | Building | 179 | Cook | 41 53 56 N | 087 37 25 W |
| John Hauberg Indian Museum | Building | 199 | Rock Island | 41 27 51 N | 090 34 18 W |
| John Hersey High School | School | 209 | Cook | 42 06 14 N | 087 57 34 W |
| John Huss United Methodist Church | Church | 183 | Cook | 41 50 54 N | 087 42 24 W |
| John Jay Elementary School | School | 210 | Cook | 42 02 28 N | 087 58 05 W |
| John Kennedy Middle Grade School | School | 189 | Kankakee | 41 06 47 N | 087 53 08 W |
| John L Coppernoll Airport | Airport | 264 | Jo Daviess | 42 18 30 N | 089 59 00 W |
| John L Nash Middle School | School | 197 | Iroquois | 40 57 35 N | 087 54 59 W |
| John L Sipley Elementary School | School | 230 | DuPage | 41 44 14 N | 088 03 01 W |
| John Laidlaw Elementary School | School | 199 | Cook | 41 48 43 N | 087 55 24 W |
| John Leigh Grammar School | School | 193 | Cook | 41 57 55 N | 087 49 53 W |
| John M Olin Nature Preserve | Park | 158 | Madison | 38 55 03 N | 090 13 02 W |
| John Mack Hollow | Valley | | Pope | 37 35 10 N | 088 39 53 W |
| John Marshall Law School | School | 182 | Cook | 41 52 40 N | 087 37 42 W |
| John Middleton Elementary School | School | 182 | Cook | 42 01 57 N | 087 43 00 W |
| John Mills Elementary School | School | 195 | Cook | 41 55 55 N | 087 49 01 W |
| John Moore Park | Park | 203 | Kendall | 41 28 48 N | 088 28 52 W |
| John Mosser Public Library | Building | 230 | Knox | 40 48 08 N | 090 23 56 W |
| John Mueller Cemetery | Cemetery | 156 | St. Clair | 38 27 08 N | 089 52 05 W |
| John Muir Elementary School | School | 244 | Cook | 42 03 40 N | 088 07 29 W |
| John Nelson Elementary School | School | 222 | Winnebago | 42 15 40 N | 089 03 57 W |
| John Philip Sousa School | School | 180 | Cook | 41 52 41 N | 087 39 15 W |
| John R Reed Airport | Airport | 210 | Coles | 39 32 57 N | 088 01 56 W |
| John R Thompson Building | Building | 180 | Cook | 41 53 20 N | 087 37 53 W |
| John R Tibbott Elementary School | School | 226 | Will | 41 42 12 N | 088 02 47 W |
| John Rich School (historical) | School | 152 | Union | 37 31 08 N | 089 13 38 W |
| John Robertson Cemetery | Cemetery | 185 | Cass | 39 56 33 N | 090 09 33 W |
| John Robinson Elementary School | School | 125 | St. Clair | 38 36 42 N | 090 09 17 W |
| John S and Hope Barnes Tennis Courts | Locale | 259 | Winnebago | 42 16 08 N | 089 01 00 W |
| John S Clark Elementary School | School | 197 | Lake | 42 23 55 N | 087 50 17 W |
| John Slifka Memorial Park | Park | 181 | Madison | 38 57 58 N | 089 45 32 W |
| John Swaney School (historical) | School | 197 | Putnam | 41 09 11 N | 089 13 08 W |
| John T McGee Middle School | School | 241 | Lake | 42 21 29 N | 088 05 38 W |
| John T McNaughton Park | Park | 151 | Tazewell | 40 35 15 N | 089 36 27 W |
| John Toman Library | Building | 181 | Cook | 41 50 31 N | 087 43 29 W |
| John W Jones Park | Park | 129 | Williamson | 37 43 27 N | 088 55 48 W |
| John W Meils RLA Airport | Airport | 214 | Marshall | 40 57 00 N | 089 07 00 W |
| John Wood Community College | School | 217 | Adams | 39 55 47 N | 091 20 25 W |
| Johnny Run | Stream | | Grundy | 41 16 58 N | 088 21 47 W |
| Johns Branch | Stream | | Marion | 38 34 16 N | 088 45 55 W |
| Johns Creek | Stream | | Sangamon | 39 37 30 N | 089 51 03 W |
| Johns Creek | Stream | | Warren | 41 00 46 N | 090 45 59 W |
| Johns Creek School (historical) | School | 190 | Sangamon | 39 35 42 N | 089 50 30 W |
| Johns Hill Magnet School | School | 218 | Macon | 39 50 17 N | 088 56 37 W |
| Johns Park | Park | 195 | Cook | 42 03 53 N | 087 48 39 W |
| Johns Quarry | Mine | 232 | Winnebago | 42 19 17 N | 089 05 22 W |
| Johns School (historical) | School | 231 | Coles | 39 26 40 N | 088 05 26 W |
| Johns Spur | Locale | 110 | Jackson | 37 40 25 N | 089 28 02 W |
| Johnsburg | Populated Place | 229 | McHenry | 42 22 48 N | 088 14 31 W |