| Hartford to Nasaud | 4,472.19 mi (7,197.29 km) |
| Hartford to Navodari | 4,756.90 mi (7,655.48 km) |
| Hartford to Negresti-Oas | 4,411.49 mi (7,099.60 km) |
| Hartford to Nehoiu | 4,623.79 mi (7,441.27 km) |
| Hartford to Ocna Mures | 4,486.52 mi (7,220.36 km) |
| Hartford to Odobesti | 4,636.08 mi (7,461.04 km) |
| Hartford to Odorheiu Secuiesc | 4,545.54 mi (7,315.34 km) |
| Hartford to Oltenita | 4,689.55 mi (7,547.10 km) |
| Hartford to Onesti | 4,604.25 mi (7,409.83 km) |
| Hartford to Oradea | 4,384.14 mi (7,055.59 km) |
| Hartford to Orastie | 4,482.06 mi (7,213.18 km) |
| Hartford to Oravita | 4,453.57 mi (7,167.34 km) |
| Hartford to Orsova | 4,494.57 mi (7,233.32 km) |
| Hartford to Otelu Rosu | 4,461.55 mi (7,180.17 km) |
| Hartford to Otopeni | 4,647.89 mi (7,480.05 km) |
