| Grottaferrata to Oegstgeest | 814.52 mi (1,310.85 km) |
| Grottaferrata to Oirschot | 755.75 mi (1,216.26 km) |
| Grottaferrata to Oisterwijk | 762.89 mi (1,227.75 km) |
| Grottaferrata to Oldebroek | 801.65 mi (1,290.13 km) |
| Grottaferrata to Oldenzaal | 775.37 mi (1,247.83 km) |
| Grottaferrata to Ommen | 796.66 mi (1,282.10 km) |
| Grottaferrata to Oosterend | 833.35 mi (1,341.14 km) |
| Grottaferrata to Oosterhout | 774.00 mi (1,245.63 km) |
| Grottaferrata to Oosterwolde | 828.72 mi (1,333.70 km) |
| Grottaferrata to Oostzaan | 820.52 mi (1,320.49 km) |
| Grottaferrata to Opmeer | 835.28 mi (1,344.25 km) |
| Grottaferrata to Oss | 767.20 mi (1,234.69 km) |
| Grottaferrata to Oud-Beijerland | 794.54 mi (1,278.68 km) |
| Grottaferrata to Oudenbosch | 778.44 mi (1,252.78 km) |
| Grottaferrata to Oudewater | 795.92 mi (1,280.91 km) |
