| Olbia to Cookeville (Tennessee) | 4,874.26 mi (7,844.37 km) |
| Olbia to Coolidge (Arizona) | 6,102.69 mi (9,821.33 km) |
| Olbia to Coon Rapids (Minnesota) | 4,817.89 mi (7,753.65 km) |
| Olbia to Cooper City (Florida) | 5,053.11 mi (8,132.19 km) |
| Olbia to Coos Bay (Oregon) | 5,940.45 mi (9,560.23 km) |
| Olbia to Copiague (New York) | 4,155.81 mi (6,688.13 km) |
| Olbia to Coppell (Texas) | 5,516.38 mi (8,877.75 km) |
| Olbia to Copperas Cove (Texas) | 5,642.78 mi (9,081.18 km) |
| Olbia to Coral Gables (Florida) | 5,066.92 mi (8,154.43 km) |
| Olbia to Coral Springs (Florida) | 5,042.29 mi (8,114.79 km) |
| Olbia to Coral Terrace (Florida) | 5,066.75 mi (8,154.15 km) |
| Olbia to Coralville (Iowa) | 4,899.21 mi (7,884.52 km) |
| Olbia to Coram (New York) | 4,131.03 mi (6,648.26 km) |
| Olbia to Corcoran (California) | 6,214.73 mi (10,001.65 km) |
| Olbia to Cordele (Georgia) | 4,970.26 mi (7,998.86 km) |
