| Gloucester City to Nuth | 3,800.51 mi (6,116.33 km) |
| Gloucester City to Oegstgeest | 3,711.84 mi (5,973.63 km) |
| Gloucester City to Oirschot | 3,762.02 mi (6,054.39 km) |
| Gloucester City to Oisterwijk | 3,755.91 mi (6,044.56 km) |
| Gloucester City to Oldebroek | 3,761.78 mi (6,054.00 km) |
| Gloucester City to Oldenzaal | 3,805.67 mi (6,124.64 km) |
| Gloucester City to Ommen | 3,780.33 mi (6,083.85 km) |
| Gloucester City to Oosterend | 3,754.44 mi (6,042.19 km) |
| Gloucester City to Oosterhout | 3,740.70 mi (6,020.07 km) |
| Gloucester City to Oosterwolde | 3,763.50 mi (6,056.77 km) |
| Gloucester City to Oostzaan | 3,722.22 mi (5,990.33 km) |
| Gloucester City to Opmeer | 3,718.35 mi (5,984.11 km) |
| Gloucester City to Oss | 3,763.89 mi (6,057.40 km) |
| Gloucester City to Oud-Beijerland | 3,718.14 mi (5,983.77 km) |
| Gloucester City to Oudenbosch | 3,728.71 mi (6,000.79 km) |
