| Holborn to Orbetello | 821.94 mi (1,322.78 km) |
| Holborn to Oria | 1,136.92 mi (1,829.70 km) |
| Holborn to Oristano | 904.26 mi (1,455.26 km) |
| Holborn to Orta Nova | 1,027.29 mi (1,653.26 km) |
| Holborn to Orte | 857.30 mi (1,379.69 km) |
| Holborn to Ortona | 929.81 mi (1,496.38 km) |
| Holborn to Orvieto | 834.62 mi (1,343.18 km) |
| Holborn to Orzinuovi | 624.07 mi (1,004.34 km) |
| Holborn to Osimo | 840.90 mi (1,353.30 km) |
| Holborn to Ospitaletto | 621.11 mi (999.59 km) |
| Holborn to Ostuni | 1,123.23 mi (1,807.67 km) |
| Holborn to Ottaviano | 1,011.60 mi (1,628.01 km) |
| Holborn to Ovada | 623.26 mi (1,003.05 km) |
| Holborn to Ozieri | 871.39 mi (1,402.37 km) |
| Holborn to Paceco | 1,119.39 mi (1,801.49 km) |
