| Gainsborough to Olympia Heights (Florida) | 4,389.47 mi (7,064.16 km) |
| Gainsborough to Omaha (Nebraska) | 4,199.15 mi (6,757.87 km) |
| Gainsborough to On Top of the World Designated Place (Florida) | 4,293.10 mi (6,909.07 km) |
| Gainsborough to Onalaska (Wisconsin) | 3,897.24 mi (6,272.01 km) |
| Gainsborough to Oneida (New York) | 3,355.11 mi (5,399.53 km) |
| Gainsborough to Oneonta (New York) | 3,359.56 mi (5,406.69 km) |
| Gainsborough to Ontario (California) | 5,314.35 mi (8,552.62 km) |
| Gainsborough to Ontario (Oregon) | 4,723.66 mi (7,601.99 km) |
| Gainsborough to Opa-locka (Florida) | 4,376.89 mi (7,043.92 km) |
| Gainsborough to Opelika (Alabama) | 4,234.31 mi (6,814.46 km) |
| Gainsborough to Opelousas (Louisiana) | 4,606.36 mi (7,413.23 km) |
| Gainsborough to Orange (California) | 5,334.73 mi (8,585.41 km) |
| Gainsborough to Orange (Texas) | 4,692.28 mi (7,551.49 km) |
| Gainsborough to Orange City (Florida) | 4,261.62 mi (6,858.42 km) |
| Gainsborough to Orangeburg (South Carolina) | 4,013.73 mi (6,459.47 km) |
