| Formia to Olympia Heights (Florida) | 5,260.71 mi (8,466.29 km) |
| Formia to Omaha (Nebraska) | 5,239.30 mi (8,431.83 km) |
| Formia to On Top of the World Designated Place (Florida) | 5,204.67 mi (8,376.10 km) |
| Formia to Onalaska (Wisconsin) | 4,934.56 mi (7,941.41 km) |
| Formia to Oneida (New York) | 4,337.81 mi (6,981.03 km) |
| Formia to Oneonta (New York) | 4,335.23 mi (6,976.88 km) |
| Formia to Ontario (California) | 6,381.78 mi (10,270.48 km) |
| Formia to Ontario (Oregon) | 5,795.09 mi (9,326.30 km) |
| Formia to Opa-locka (Florida) | 5,248.98 mi (8,447.42 km) |
| Formia to Opelika (Alabama) | 5,189.34 mi (8,351.44 km) |
| Formia to Opelousas (Louisiana) | 5,583.00 mi (8,984.97 km) |
| Formia to Orange (California) | 6,402.18 mi (10,303.31 km) |
| Formia to Orange (Texas) | 5,675.02 mi (9,133.05 km) |
| Formia to Orange City (Florida) | 5,165.42 mi (8,312.93 km) |
| Formia to Orangeburg (South Carolina) | 4,949.94 mi (7,966.15 km) |
