Feature Name | Class | Elev. meters | County | Latitude DMS | Longitude DMS |
| Gumm Lake Dam | Dam | 206 | Edgar | 39 32 00 N | 087 44 30 W |
| Gun Club Lake | Reservoir | 215 | Will | 41 30 18 N | 087 54 00 W |
| Gun Club Ponds | Lake | | Cook | 41 40 14 N | 087 33 57 W |
| Gun Creek | Stream | | Franklin | 38 04 51 N | 088 57 42 W |
| Gun Creek Public Use Area | Park | 131 | Franklin | 38 04 55 N | 088 55 50 W |
| Gundlach Mines | Mine | 146 | St. Clair | 38 36 49 N | 090 02 30 W |
| Gunds Cemetery | Cemetery | 252 | Stephenson | 42 16 47 N | 089 31 10 W |
| Gundy Cemetery | Cemetery | 193 | Vermilion | 40 16 15 N | 087 38 33 W |
| Gunion Christian Church | Church | 132 | Wayne | 38 32 37 N | 088 23 03 W |
| Gunion School (historical) | School | 137 | Wayne | 38 31 47 N | 088 23 01 W |
| Gunn School (historical) | School | 237 | DeKalb | 42 07 24 N | 088 54 00 W |
| Gunnar Anderson County Forest Preserve | Park | 215 | Kane | 41 52 45 N | 088 18 31 W |
| Gunning Cemetery | Cemetery | 195 | McDonough | 40 18 18 N | 090 42 05 W |
| Gunsaulus Scholastic Academy | School | 182 | Cook | 41 48 45 N | 087 41 59 W |
| Gunsolas School | School | 256 | Winnebago | 42 12 06 N | 089 01 58 W |
| Gunter Cemetery | Cemetery | 138 | Hamilton | 38 05 07 N | 088 36 41 W |
| Gunter School (historical) | School | 136 | Hamilton | 38 04 54 N | 088 36 43 W |
| Gunterman Cemetery | Cemetery | 205 | Jersey | 39 07 51 N | 090 31 30 W |
| Gunterman School (historical) | School | 201 | Jersey | 39 07 48 N | 090 30 59 W |
| Gurgens Park | Park | 158 | Sangamon | 39 52 15 N | 089 38 33 W |
| Gurley Cemetery | Cemetery | 131 | Johnson | 37 31 12 N | 089 00 20 W |
| Gurley Ditch | Canal | 105 | Massac | 37 15 54 N | 088 44 42 W |
| Gurnee | Populated Place | 207 | Lake | 42 22 13 N | 087 54 07 W |
| Gurnee Grade School | School | 201 | Lake | 42 22 26 N | 087 55 06 W |
| Gurnee Village Hall | Building | 204 | Lake | 42 21 53 N | 087 54 51 W |
| Gurnee Woods Forest Preserve | Forest | 203 | Lake | 42 24 09 N | 087 55 36 W |
| Gurney (historical) | Populated Place | 192 | Cass | 39 53 57 N | 090 03 00 W |
| Gurney Mills | Locale | 222 | Lake | 42 23 15 N | 087 57 16 W |
| Gurney School (historical) | School | 192 | Cass | 39 53 41 N | 090 03 02 W |
| Gurney School (historical) | School | 209 | Will | 41 23 36 N | 088 04 40 W |
| Gurrie Middle School | School | 199 | Cook | 41 47 42 N | 087 52 27 W |
| Gurudawara Sikh Religious Society | Church | 249 | Cook | 42 07 52 N | 088 04 32 W |
| Guss School (historical) | School | 186 | Pike | 39 44 31 N | 091 05 25 W |
| Guth Cemetery | Cemetery | 217 | Tazewell | 40 41 33 N | 089 29 09 W |
| Guthrie | Populated Place | 246 | Ford | 40 30 30 N | 088 19 30 W |
| Guthrie Park | Park | 188 | Cook | 41 49 36 N | 087 49 13 W |
| Guthrie School (historical) | School | 248 | Ford | 40 30 06 N | 088 19 44 W |
| Guthrie School (historical) | School | 192 | Montgomery | 39 21 45 N | 089 34 05 W |
| Guy Cemetery | Cemetery | 183 | Fayette | 39 01 15 N | 088 51 45 W |
| Guy Cemetery | Cemetery | 214 | McDonough | 40 30 02 N | 090 45 25 W |
| Guy School (historical) | School | 212 | McDonough | 40 30 25 N | 090 46 07 W |
| Guyer Cemetery | Cemetery | 153 | Crawford | 39 08 51 N | 087 42 41 W |
| Gvillo Pond | Reservoir | 151 | Madison | 38 52 12 N | 090 03 36 W |
| Gvillo Pond Dam | Dam | 151 | Madison | 38 52 12 N | 090 03 36 W |
| Gwinn Cemetery | Cemetery | 210 | Douglas | 39 42 27 N | 088 02 32 W |
| Gymnastic Academy of Rockford | School | 270 | Winnebago | 42 18 23 N | 088 59 02 W |
| Gymon Cemetery | Cemetery | 195 | Edgar | 39 32 57 N | 087 34 45 W |
| Gyp Williams Hollow | Valley | | Pope | 37 33 52 N | 088 27 32 W |
| H A Peine Memorial Library | Building | 194 | Tazewell | 40 26 05 N | 089 18 52 W |
| H C Storm Elementary School | School | 222 | Kane | 41 51 15 N | 088 19 22 W |
| H G Rice Park | Park | 143 | Mason | 40 17 55 N | 090 03 20 W |
| H H Conrady Junior High School | School | 186 | Cook | 41 42 57 N | 087 48 59 W |
| H Meeker Airport | Airport | 146 | Hancock | 40 15 15 N | 091 26 25 W |
| H R McCall Elementary School | School | 211 | Lake | 42 24 38 N | 087 51 51 W |
| Haas Park | Park | 182 | Cook | 41 55 30 N | 087 41 44 W |
| Haas Quarry | Mine | 217 | Carroll | 42 09 28 N | 090 05 05 W |
| Habbes Lake | Reservoir | 155 | Washington | 38 18 06 N | 089 23 06 W |
| Habbes Lake Dam | Dam | 155 | Washington | 38 18 06 N | 089 23 06 W |
| Habecker Bridge | Bridge | 229 | McLean | 40 31 54 N | 089 11 29 W |
| Hack Cemetery | Cemetery | 206 | Pike | 39 25 34 N | 090 46 25 W |
| Hackberry Island | Island | 227 | Lake | 42 27 44 N | 088 10 06 W |
| Hackberry School (historical) | School | 151 | Pike | 39 28 20 N | 090 46 57 W |
| Hackberry School (historical) | School | 184 | Shelby | 39 21 02 N | 088 49 14 W |
| Hackberry Slough | Stream | | Whiteside | 41 41 16 N | 089 54 19 W |
| Hacke Cemetery | Cemetery | 184 | Macoupin | 39 12 35 N | 089 54 18 W |
| Hacker Bend | Bend | 103 | Alexander | 37 15 01 N | 089 27 00 W |
| Hacker RLA Airport | Airport | 196 | Montgomery | 39 14 40 N | 089 25 33 W |
| Hackett Branch | Stream | | Douglas | 39 45 36 N | 088 14 27 W |
| Hackley Island | Island | 148 | Hancock | 40 17 17 N | 091 28 48 W |
| Hackman Cemetery | Cemetery | 144 | Cass | 39 53 52 N | 090 23 37 W |
| Hadaway Slough | Stream | | Whiteside | 41 37 40 N | 090 04 40 W |
| Hadden Cemetery | Cemetery | 162 | Marion | 38 40 03 N | 088 48 14 W |
| Hadden Cemetery | Cemetery | 127 | White | 38 07 34 N | 088 09 26 W |
| Hadden School (historical) | School | 133 | White | 38 07 34 N | 088 08 58 W |
| Haddock School (historical) | School | 189 | Cumberland | 39 22 18 N | 088 08 20 W |
| Hadley | Populated Place | 153 | Lawrence | 38 43 10 N | 087 54 31 W |
| Hadley | Populated Place | 227 | Pike | 39 42 20 N | 090 58 21 W |
| Hadley | Populated Place | 226 | Will | 41 34 15 N | 087 56 38 W |
| Hadley Cemetery | Cemetery | 204 | Livingston | 41 01 22 N | 088 39 35 W |
| Hadley Cemetery | Cemetery | 225 | Will | 41 33 54 N | 087 57 09 W |
| Hadley Creek | Stream | | Pike | 39 39 55 N | 091 09 12 W |
| Hadley Creek Number 2 Dam | Dam | 238 | Adams | 39 47 06 N | 091 01 36 W |
| Hadley Creek Number 2 Reservoir | Reservoir | 238 | Adams | 39 47 06 N | 091 01 36 W |
| Hadley Landing Public Access Area | Locale | 128 | Calhoun | 39 02 46 N | 090 35 24 W |
| Hadley School | School | 232 | Will | 41 36 08 N | 087 55 37 W |
| Hadley School (historical) | School | 151 | Lawrence | 38 42 48 N | 087 53 26 W |
| Hadley School (historical) | School | 210 | Will | 41 33 59 N | 087 57 29 W |
| Hadley School for the Blind | School | 195 | Cook | 42 06 20 N | 087 43 49 W |
| Hadley-McCraney Diversion Ditch | Canal | 138 | Pike | 39 37 49 N | 091 09 55 W |
| Haedicke Cemetery | Cemetery | 190 | Woodford | 40 45 17 N | 089 29 15 W |
| Haedtler Landing Strip (historical) | Airport | 228 | Will | 41 28 09 N | 087 43 25 W |
| Haeger Cemetery | Cemetery | 256 | McHenry | 42 10 06 N | 088 13 12 W |
| Haeger School (historical) | School | 256 | McHenry | 42 10 06 N | 088 13 10 W |
| Haegers Bend | Populated Place | 224 | McHenry | 42 11 20 N | 088 15 38 W |
| Hafer Baptist Church | Church | 131 | Williamson | 37 46 37 N | 089 02 58 W |
| Hagaman | Populated Place | 159 | Macoupin | 39 18 37 N | 090 04 41 W |
| Hagan School (historical) | School | 206 | McDonough | 40 24 42 N | 090 45 46 W |
| Hagarstown | Populated Place | 162 | Fayette | 38 56 36 N | 089 10 06 W |
| Hagarstown Post Office | Post Office | 162 | Fayette | 38 56 35 N | 089 10 06 W |
| Hageman Cemetery | Cemetery | 211 | McDonough | 40 35 09 N | 090 35 16 W |
| Hagemann Creek | Stream | | St. Clair | 38 37 22 N | 089 50 31 W |
| Hagemeister Landing Strip | Airport | 201 | Adams | 40 11 09 N | 091 18 51 W |
| Hagener | Populated Place | 145 | Cass | 39 55 33 N | 090 23 50 W |
| Hagener Townhall | Building | 141 | Cass | 39 55 09 N | 090 27 27 W |
| Hager Cemetery | Cemetery | 142 | Cass | 40 01 46 N | 090 17 34 W |
| Hager Slough | Gut | 132 | Cass | 40 02 51 N | 090 23 37 W |
| Hagerman Cemetery | Cemetery | 201 | Moultrie | 39 37 24 N | 088 34 42 W |
| Hagerty Mine (historical) | Mine | 209 | Jo Daviess | 42 19 52 N | 090 14 32 W |
| Haggard Cemetery | Cemetery | 129 | Perry | 38 02 19 N | 089 11 49 W |
| Haggins Cemetery | Cemetery | 180 | Cumberland | 39 19 51 N | 088 15 29 W |