| Name | What | Region | Country | Lat | Long | Elev ft. | Pop est |
|---|---|---|---|---|---|---|---|
| Claiborne | city | Ohio | United States | 40.39 | -83.35 | 964 | |
| Clare | city | Ohio | United States | 39.14 | -84.38 | 830 | |
| Claremont | city | Ohio | United States | 40.05 | -80.86 | 898 | |
| Claridon | city | Ohio | United States | 40.58 | -83.00 | 961 | |
| Claridon | city | Ohio | United States | 41.54 | -81.13 | 1213 | |
| Clarington | city | Ohio | United States | 39.77 | -80.87 | 830 | |
| Clarion | city | Ohio | United States | 39.09 | -82.38 | 830 | |
| Clark | city | Ohio | United States | 40.01 | -84.72 | 1108 | |
| Clark | city | Ohio | United States | 40.45 | -81.90 | 895 | |
| Clark Corners | city | Ohio | United States | 41.06 | -81.73 | 1049 | |
| Clarks | city | Ohio | United States | 41.59 | -81.21 | 1223 | |
| Clarks (historical) | city | Ohio | United States | 41.65 | -81.24 | 1010 | |
| Clarksburg | city | Ohio | United States | 39.51 | -83.15 | 830 | |
| Clarksfield | city | Ohio | United States | 41.20 | -82.41 | 898 | |
| Clarkson | city | Ohio | United States | 40.75 | -80.61 | 1197 | |
| Clarksville | city | Ohio | United States | 39.40 | -83.98 | 892 | |
| Clarksville | city | Ohio | United States | 39.71 | -82.29 | 905 | |
| Clarksville (historical) | city | Ohio | United States | 41.42 | -84.77 | 843 | |
| Clarktown | city | Ohio | United States | 38.85 | -82.91 | 964 | |
| Clay | city | Ohio | United States | 38.94 | -82.57 | 830 | |
| Clay Center | city | Ohio | United States | 41.56 | -83.36 | 830 | |
| Claybank (historical) | city | Ohio | United States | 39.68 | -82.18 | 997 | |
| Claybaugh Trailer Park | city | Ohio | United States | 41.11 | -84.00 | 830 | |
| Claybrooke Crossings | city | Ohio | United States | 39.86 | -83.09 | 830 | |
| Claylick | city | Ohio | United States | 40.06 | -82.29 | 872 | |
| Claypools (historical) | city | Ohio | United States | 40.04 | -82.17 | 895 | |
| Claysburg (historical) | city | Ohio | United States | 39.63 | -84.76 | 997 | |
| Claysville | city | Ohio | United States | 39.94 | -81.67 | 997 | |
| Clayton | city | Ohio | United States | 38.74 | -83.68 | 902 | |
| Clayton | city | Ohio | United States | 39.86 | -84.36 | 994 | |
| Clayton | city | Ohio | United States | 40.15 | -84.38 | 948 | |
| Clear View Heights | city | Ohio | United States | 40.79 | -81.33 | 1095 | |
| Clearfork Mobile Home Park | city | Ohio | United States | 40.60 | -82.46 | 1118 | |
| Clearport | city | Ohio | United States | 39.62 | -82.68 | 898 | |
| Clearview | city | Ohio | United States | 38.45 | -82.60 | 830 | |
| Clearview | city | Ohio | United States | 40.82 | -81.52 | 1085 | |
| Clearview | city | Ohio | United States | 39.30 | -82.12 | 882 | |
| Clearview | city | Ohio | United States | 39.32 | -84.35 | 898 | |
| Clearview Mobile Home Park | city | Ohio | United States | 39.91 | -83.86 | 902 | |
| Clearview Mobile Home Park | city | Ohio | United States | 40.40 | -81.40 | 889 | |
| Clearview Mobile Park | city | Ohio | United States | 41.43 | -82.17 | 830 | |
| Clearwater Trailer Park | city | Ohio | United States | 41.06 | -83.66 | 830 | |
| Clearwood Court | city | Ohio | United States | 40.83 | -80.56 | 1089 | |
| Clement | city | Ohio | United States | 39.74 | -84.11 | 898 | |
| Clemma (historical) | city | Ohio | United States | 38.63 | -82.20 | 830 | |
| Clems Shady Nook Park | city | Ohio | United States | 38.73 | -83.83 | 830 | |
| Clendening (historical) | city | Ohio | United States | 40.25 | -81.21 | 997 | |
| Clermontville | city | Ohio | United States | 38.92 | -84.25 | 830 | |
| Clertoma | city | Ohio | United States | 39.17 | -84.28 | 830 | |
| Cleveland | city | Ohio | United States | 41.50 | -81.70 | 830 | |
| Cleveland Heights | city | Ohio | United States | 41.52 | -81.56 | 948 | |
| Clevengers (historical) | city | Ohio | United States | 40.96 | -84.18 | 830 | |
| Cleves | city | Ohio | United States | 39.16 | -84.75 | 830 | |
| Clifford | city | Ohio | United States | 38.93 | -83.02 | 830 | |
| Cliffyville (historical) | city | Ohio | United States | 39.71 | -81.33 | 997 | |
| Clifton | city | Ohio | United States | 39.80 | -83.83 | 997 | |
| Clifton | city | Ohio | United States | 39.15 | -84.52 | 830 | |
| Clifton | city | Ohio | United States | 39.54 | -81.55 | 830 | |
| Clifton Chase | city | Ohio | United States | 39.93 | -83.15 | 898 | |
| Clifton Heights | city | Ohio | United States | 39.14 | -84.52 | 830 | |
| Clifton Park | city | Ohio | United States | 41.49 | -81.80 | 830 | |
| Climax | city | Ohio | United States | 40.63 | -82.89 | 1036 | |
| Cline | city | Ohio | United States | 39.61 | -81.16 | 912 | |
| Cline Mobile Park | city | Ohio | United States | 40.61 | -80.65 | 830 | |
| Clinton | city | Ohio | United States | 40.04 | -82.96 | 830 | |
| Clinton | city | Ohio | United States | 40.93 | -81.63 | 997 | |
| Clinton | city | Ohio | United States | 39.47 | -83.75 | 1046 | |
| Clinton (historical) | city | Ohio | United States | 40.41 | -82.50 | 1066 | |
| Clinton Mobile Home Court | city | Ohio | United States | 41.12 | -83.16 | 830 | |
| Clio (historical) | city | Ohio | United States | 40.08 | -81.50 | 875 | |
| Clipper Mills | city | Ohio | United States | 38.76 | -82.21 | 830 | |
| Clivdon | city | Ohio | United States | 40.08 | -82.83 | 980 | |
| Clivdon Mews | city | Ohio | United States | 40.07 | -82.83 | 980 | |
| Cloud (historical) | city | Ohio | United States | 39.73 | -81.75 | 830 | |
| Clough Heights | city | Ohio | United States | 39.09 | -84.30 | 898 | |
| Clover | city | Ohio | United States | 39.00 | -84.04 | 895 | |
| Clover Hill | city | Ohio | United States | 39.78 | -82.16 | 1000 | |
| Clover Hill | city | Ohio | United States | 41.49 | -80.88 | 902 | |
| Clover Hill | city | Ohio | United States | 39.87 | -80.92 | 1197 | |
| Clover Leaf Mobile Home Park | city | Ohio | United States | 41.27 | -81.83 | 1049 | |
| Clover Trailer Park | city | Ohio | United States | 40.26 | -81.87 | 830 | |
| Cloverdale | city | Ohio | United States | 41.34 | -83.57 | 830 | |
| Cloverdale | city | Ohio | United States | 41.02 | -84.30 | 830 | |
| Cloverdale | city | Ohio | United States | 40.82 | -81.49 | 1095 | |
| Cloverdale | city | Ohio | United States | 40.03 | -84.19 | 862 | |
| Cloverleaf (historical) | city | Ohio | United States | 41.47 | -84.08 | 830 | |
| Clowville (historical) | city | Ohio | United States | 40.24 | -81.86 | 830 | |
| Club Island | city | Ohio | United States | 40.51 | -84.48 | 875 | |
| Clyde | city | Ohio | United States | 41.30 | -82.98 | 830 |