Feature Name | Class | Elev. meters | County | Latitude DMS | Longitude DMS |
| Concord Woods Nature Park | Park | 257 | Lake | 41 40 35 N | 081 14 13 W |
| Concordia Evangelical Lutheran Church | Church | 317 | Mahoning | 41 06 20 N | 080 41 37 W |
| Concordia Evangelical Lutheran Church | Church | 317 | Summit | 41 03 48 N | 081 30 55 W |
| Concordia Lutheran Church | Church | 267 | Cuyahoga | 41 27 50 N | 081 36 25 W |
| Concordia Lutheran Church | Church | 278 | Franklin | 39 57 25 N | 083 07 60 W |
| Concordia Lutheran Church | Church | 167 | Hamilton | 39 08 47 N | 084 32 10 W |
| Concordia Lutheran Church | Church | 190 | Lucas | 41 36 00 N | 083 36 37 W |
| Concordia Lutheran Church | Church | 292 | Montgomery | 39 42 37 N | 084 10 01 W |
| Concordia Lutheran Church | Church | 329 | Wayne | 40 49 43 N | 081 57 33 W |
| Concordia School | School | 170 | Hamilton | 39 08 46 N | 084 32 09 W |
| Concordia School | School | 189 | Lucas | 41 36 07 N | 083 36 35 W |
| Concourse 7075 Industrial Park | Locale | 226 | Montgomery | 39 48 03 N | 084 10 12 W |
| Condeville | Populated Place | 178 | Meigs | 38 57 07 N | 081 54 30 W |
| Condeville Methodist Church | Church | 176 | Meigs | 38 57 03 N | 081 54 29 W |
| Condin Ditch | Canal | 178 | Lucas | 41 40 01 N | 083 25 07 W |
| Condit | Populated Place | 330 | Delaware | 40 15 36 N | 082 47 17 W |
| Condit Post Office (historical) | Post Office | 330 | Delaware | 40 15 35 N | 082 47 15 W |
| Condit United Presbyterian Church | Church | 329 | Delaware | 40 14 51 N | 082 47 22 W |
| Condon Cemetery | Cemetery | 177 | Pike | 39 08 44 N | 082 55 32 W |
| Condon School | School | 225 | Hamilton | 39 08 41 N | 084 30 04 W |
| Cone Reef | Bar | 174 | Ottawa | 41 40 00 N | 083 02 42 W |
| Cones Landing | Locale | 183 | Washington | 39 21 41 N | 081 31 36 W |
| Conesville | Populated Place | 227 | Coshocton | 40 11 02 N | 081 53 27 W |
| Conesville Elementary School | School | 239 | Coshocton | 40 11 18 N | 081 53 39 W |
| Conesville Post Office | Post Office | 228 | Coshocton | 40 11 03 N | 081 53 32 W |
| Conesville Post Office | Post Office | 227 | Coshocton | 40 11 00 N | 081 53 29 W |
| Coney Island Wharf (historical) | Locale | 140 | Hamilton | 39 05 47 N | 084 30 19 W |
| Confederate Cemetery | Cemetery | 177 | Ottawa | 41 30 01 N | 082 43 48 W |
| Confederate Crossroads (historical) | Populated Place | 238 | Muskingum | 39 50 12 N | 081 51 28 W |
| Confidence Cemetery | Cemetery | 292 | Brown | 38 53 07 N | 083 53 60 W |
| Confusion Run | Stream | | Trumbull | 41 17 27 N | 080 45 15 W |
| Congo | Populated Place | 270 | Perry | 39 36 55 N | 082 07 18 W |
| Congo Creek | Stream | | Pickaway | 39 31 26 N | 082 58 15 W |
| Congo Post Office (historical) | Post Office | 275 | Perry | 39 36 55 N | 082 07 20 W |
| Congregation for Reconciliation | Church | 264 | Montgomery | 39 46 31 N | 084 13 20 W |
| Congregation of the Tabernacle | Church | 233 | Montgomery | 39 45 50 N | 084 12 36 W |
| Congregation Ohav Shalom | Church | 179 | Hamilton | 39 11 52 N | 084 27 20 W |
| Congregation Rodef Sholom | Church | 308 | Mahoning | 41 06 54 N | 080 38 42 W |
| Congregational Cemetery | Cemetery | 254 | Jackson | 38 53 35 N | 082 33 37 W |
| Congregational Christian Church | Church | 267 | Miami | 40 09 02 N | 084 14 42 W |
| Congregational Church of Christ | Church | 248 | Lorain | 41 17 40 N | 082 13 06 W |
| Congregational United Church of Christ | Church | 235 | Fulton | 41 32 55 N | 084 08 34 W |
| Congress | Populated Place | 354 | Wayne | 40 55 33 N | 082 03 11 W |
| Congress Cemetery | Cemetery | 361 | Wayne | 40 55 51 N | 082 03 14 W |
| Congress Community Church | Church | 364 | Wayne | 40 55 43 N | 082 03 08 W |
| Congress Creek | Stream | | Washington | 39 17 20 N | 081 33 57 W |
| Congress Elementary School | School | 359 | Wayne | 40 55 29 N | 082 03 16 W |
| Congress Furnace (historical) | Locale | 300 | Stark | 40 44 31 N | 081 22 02 W |
| Congress Lake | Lake | 350 | Stark | 40 58 30 N | 081 19 29 W |
| Congress Lake (historical) | Populated Place | 353 | Stark | 40 58 40 N | 081 19 47 W |
| Congress Lake Dam | Dam | 354 | Stark | 40 58 30 N | 081 19 29 W |
| Congress Lake Golf Club | Locale | 352 | Stark | 40 58 31 N | 081 19 27 W |
| Congress Lake Outlet | Stream | | Portage | 41 03 10 N | 081 16 19 W |
| Congress Landing | Locale | 182 | Washington | 39 17 17 N | 081 33 58 W |
| Congress Run | Stream | | Athens | 39 28 57 N | 082 04 40 W |
| Congress Run | Stream | | Hamilton | 39 12 14 N | 084 29 08 W |
| Congress Run | Stream | | Washington | 39 32 56 N | 081 36 30 W |
| Conkles Hollow | Valley | | Hocking | 39 27 16 N | 082 34 29 W |
| Conkles Hollow Picnic Area | Locale | 282 | Hocking | 39 27 19 N | 082 34 35 W |
| Conkles Hollow Recreation Area | Park | 310 | Hocking | 39 27 25 N | 082 34 43 W |
| Conkles Hollow State Nature Preserve | Park | 233 | Hocking | 39 27 25 N | 082 34 34 W |
| Conklin Airport | Airport | 205 | Wood | 41 23 30 N | 083 42 12 W |
| Conklin Cemetery | Cemetery | 245 | Pickaway | 39 46 33 N | 082 51 33 W |
| Conklin Hall | Building | 207 | Wood | 41 22 33 N | 083 38 01 W |
| Conklin Hollow | Valley | | Scioto | 38 43 18 N | 083 08 34 W |
| Conley Cemetery | Cemetery | 370 | Richland | 40 33 19 N | 082 30 37 W |
| Conley Cemetery | Cemetery | 222 | Scioto | 38 46 50 N | 083 02 42 W |
| Conn Church | Church | 268 | Perry | 39 33 36 N | 082 07 11 W |
| Conn Church Cemetery | Cemetery | 269 | Perry | 39 33 35 N | 082 07 12 W |
| Conn School (historical) | School | 264 | Brown | 38 51 02 N | 083 49 31 W |
| Conneaut | Populated Place | 197 | Ashtabula | 41 56 51 N | 080 33 15 W |
| Conneaut Boat Club | Locale | 174 | Ashtabula | 41 58 12 N | 080 33 07 W |
| Conneaut Carnegie Library | Building | 201 | Ashtabula | 41 56 39 N | 080 33 25 W |
| Conneaut City Hall | Building | 200 | Ashtabula | 41 56 34 N | 080 33 25 W |
| Conneaut Creek | Stream | | Ashtabula | 41 58 11 N | 080 32 53 W |
| Conneaut Elementary School | School | 208 | Wood | 41 22 47 N | 083 39 46 W |
| Conneaut Harbor | Bay | 174 | Ashtabula | 41 58 30 N | 080 33 12 W |
| Conneaut High School | School | 201 | Ashtabula | 41 56 48 N | 080 33 42 W |
| Conneaut Municipal Water Works | Locale | 191 | Ashtabula | 41 57 35 N | 080 34 21 W |
| Conneaut Park | Park | 186 | Ashtabula | 41 57 43 N | 080 33 45 W |
| Conneaut Plaza Shopping Center | Locale | 205 | Ashtabula | 41 56 23 N | 080 35 15 W |
| Conneaut Post Office | Post Office | 201 | Ashtabula | 41 56 39 N | 080 33 23 W |
| Conneaut United Congregationalist Church | Church | 200 | Ashtabula | 41 56 34 N | 080 33 27 W |
| Connecting Ridge | Ridge | 423 | Monroe | 39 40 12 N | 080 54 58 W |
| Connelly Field | Park | 189 | Lucas | 41 38 27 N | 083 35 39 W |
| Conner Branch | Stream | | Greene | 39 45 12 N | 083 55 26 W |
| Conner Ridge | Ridge | 351 | Monroe | 39 42 18 N | 081 10 56 W |
| Conner-Kaiser Cemetery | Cemetery | 278 | Auglaize | 40 36 25 N | 084 06 36 W |
| Conners Ridge Cemetery | Cemetery | 339 | Monroe | 39 42 06 N | 081 09 40 W |
| Connett | Populated Place | 270 | Athens | 39 24 41 N | 082 15 17 W |
| Connett Cemetery | Cemetery | 280 | Athens | 39 24 56 N | 082 15 24 W |
| Connor | Populated Place | 207 | Jefferson | 40 11 20 N | 080 42 47 W |
| Connor Cemetery | Cemetery | 356 | Champaign | 40 12 04 N | 083 55 15 W |
| Connor Cemetery | Cemetery | 306 | Union | 40 09 28 N | 083 28 27 W |
| Connor Ridge Methodist Church | Church | 341 | Monroe | 39 42 04 N | 081 09 38 W |
| Connor School (historical) | School | 315 | Fayette | 39 27 09 N | 083 32 52 W |
| Connorville | Populated Place | 211 | Jefferson | 40 11 34 N | 080 42 47 W |
| Connorville Post Office (historical) | Post Office | 206 | Jefferson | 40 11 35 N | 080 42 49 W |
| Conotton | Populated Place | 292 | Harrison | 40 25 02 N | 081 08 47 W |
| Conotton Cemetery | Cemetery | 324 | Harrison | 40 24 37 N | 081 08 55 W |
| Conotton Creek | Stream | | Tuscarawas | 40 34 34 N | 081 23 32 W |
| Conotton Post Office (historical) | Post Office | 294 | Harrison | 40 25 00 N | 081 08 49 W |
| Conotton Valley High School | School | 288 | Carroll | 40 27 45 N | 081 13 08 W |
| Conover | Populated Place | 344 | Miami | 40 08 07 N | 084 02 47 W |
| Conover Hospital | Hospital | 231 | Warren | 39 33 31 N | 084 16 36 W |
| Conover Post Office | Post Office | 345 | Miami | 40 08 05 N | 084 02 45 W |
| Conquer Hill School (historical) | School | 299 | Guernsey | 39 58 31 N | 081 30 29 W |
| Conrad Cemeteries | Cemetery | 297 | Fairfield | 39 36 56 N | 082 45 25 W |
| Conrad Cemetery | Cemetery | 329 | Wayne | 40 53 17 N | 081 45 21 W |
| Conrad Elementary School | School | 259 | Licking | 40 03 50 N | 082 23 16 W |