| Hackettstown to Nuth | 3,745.89 mi (6,028.42 km) |
| Hackettstown to Oegstgeest | 3,656.48 mi (5,884.54 km) |
| Hackettstown to Oirschot | 3,707.05 mi (5,965.92 km) |
| Hackettstown to Oisterwijk | 3,700.90 mi (5,956.02 km) |
| Hackettstown to Oldebroek | 3,705.94 mi (5,964.13 km) |
| Hackettstown to Oldenzaal | 3,749.74 mi (6,034.62 km) |
| Hackettstown to Ommen | 3,724.33 mi (5,993.73 km) |
| Hackettstown to Oosterend | 3,698.14 mi (5,951.58 km) |
| Hackettstown to Oosterhout | 3,685.70 mi (5,931.56 km) |
| Hackettstown to Oosterwolde | 3,707.16 mi (5,966.10 km) |
| Hackettstown to Oostzaan | 3,666.58 mi (5,900.79 km) |
| Hackettstown to Opmeer | 3,662.49 mi (5,894.21 km) |
| Hackettstown to Oss | 3,708.66 mi (5,968.52 km) |
| Hackettstown to Oud-Beijerland | 3,663.10 mi (5,895.18 km) |
| Hackettstown to Oudenbosch | 3,673.83 mi (5,912.45 km) |
