| Gloucester City to Orbetello | 4,285.74 mi (6,897.24 km) |
| Gloucester City to Oria | 4,638.73 mi (7,465.32 km) |
| Gloucester City to Oristano | 4,254.74 mi (6,847.34 km) |
| Gloucester City to Orta Nova | 4,523.33 mi (7,279.59 km) |
| Gloucester City to Orte | 4,336.74 mi (6,979.31 km) |
| Gloucester City to Ortona | 4,428.77 mi (7,127.42 km) |
| Gloucester City to Orvieto | 4,315.63 mi (6,945.34 km) |
| Gloucester City to Orzinuovi | 4,131.25 mi (6,648.60 km) |
| Gloucester City to Osimo | 4,348.68 mi (6,998.52 km) |
| Gloucester City to Ospitaletto | 4,132.24 mi (6,650.20 km) |
| Gloucester City to Ostuni | 4,627.61 mi (7,447.42 km) |
| Gloucester City to Ottaviano | 4,486.78 mi (7,220.78 km) |
| Gloucester City to Ovada | 4,100.00 mi (6,598.31 km) |
| Gloucester City to Ozieri | 4,250.26 mi (6,840.13 km) |
| Gloucester City to Paceco | 4,505.45 mi (7,250.83 km) |
