| Pirot to Olympia Heights (Florida) | 5,622.91 mi (9,049.19 km) |
| Pirot to Omaha (Nebraska) | 5,468.75 mi (8,801.11 km) |
| Pirot to On Top of the World Designated Place (Florida) | 5,545.79 mi (8,925.09 km) |
| Pirot to Onalaska (Wisconsin) | 5,168.83 mi (8,318.43 km) |
| Pirot to Oneida (New York) | 4,629.50 mi (7,450.46 km) |
| Pirot to Oneonta (New York) | 4,632.41 mi (7,455.15 km) |
| Pirot to Ontario (California) | 6,541.63 mi (10,527.73 km) |
| Pirot to Ontario (Oregon) | 5,916.91 mi (9,522.35 km) |
| Pirot to Opa-locka (Florida) | 5,610.73 mi (9,029.60 km) |
| Pirot to Opelika (Alabama) | 5,503.15 mi (8,856.46 km) |
| Pirot to Opelousas (Louisiana) | 5,881.04 mi (9,464.63 km) |
| Pirot to Orange (California) | 6,561.78 mi (10,560.17 km) |
| Pirot to Orange (Texas) | 5,968.05 mi (9,604.65 km) |
| Pirot to Orange City (Florida) | 5,510.73 mi (8,868.67 km) |
| Pirot to Orangeburg (South Carolina) | 5,275.71 mi (8,490.44 km) |
