| Ithaca to Olympia Heights (Florida) | 1,175.57 mi (1,891.90 km) |
| Ithaca to Omaha (Nebraska) | 1,007.18 mi (1,620.90 km) |
| Ithaca to On Top of the World Designated Place (Florida) | 976.32 mi (1,571.23 km) |
| Ithaca to Onalaska (Wisconsin) | 746.69 mi (1,201.68 km) |
| Ithaca to Oneida (New York) | 61.08 mi (98.30 km) |
| Ithaca to Oneonta (New York) | 73.24 mi (117.87 km) |
| Ithaca to Ontario (California) | 2,281.00 mi (3,670.92 km) |
| Ithaca to Ontario (Oregon) | 2,019.69 mi (3,250.37 km) |
| Ithaca to Opa-locka (Florida) | 1,162.73 mi (1,871.23 km) |
| Ithaca to Opelika (Alabama) | 831.50 mi (1,338.17 km) |
| Ithaca to Opelousas (Louisiana) | 1,190.94 mi (1,916.63 km) |
| Ithaca to Orange (California) | 2,299.43 mi (3,700.58 km) |
| Ithaca to Orange (Texas) | 1,279.39 mi (2,058.97 km) |
| Ithaca to Orange City (Florida) | 970.82 mi (1,562.38 km) |
| Ithaca to Orangeburg (South Carolina) | 662.33 mi (1,065.92 km) |
