| Castellammare del Golfo to Oegstgeest | 1,059.02 mi (1,704.33 km) |
| Castellammare del Golfo to Oirschot | 1,001.16 mi (1,611.21 km) |
| Castellammare del Golfo to Oisterwijk | 1,008.18 mi (1,622.51 km) |
| Castellammare del Golfo to Oldebroek | 1,051.64 mi (1,692.46 km) |
| Castellammare del Golfo to Oldenzaal | 1,028.11 mi (1,654.58 km) |
| Castellammare del Golfo to Ommen | 1,048.31 mi (1,687.09 km) |
| Castellammare del Golfo to Oosterend | 1,084.93 mi (1,746.03 km) |
| Castellammare del Golfo to Oosterhout | 1,018.18 mi (1,638.60 km) |
| Castellammare del Golfo to Oosterwolde | 1,080.88 mi (1,739.52 km) |
| Castellammare del Golfo to Oostzaan | 1,067.21 mi (1,717.50 km) |
| Castellammare del Golfo to Opmeer | 1,082.90 mi (1,742.76 km) |
| Castellammare del Golfo to Oss | 1,014.21 mi (1,632.21 km) |
| Castellammare del Golfo to Oud-Beijerland | 1,037.56 mi (1,669.78 km) |
| Castellammare del Golfo to Oudenbosch | 1,021.13 mi (1,643.35 km) |
| Castellammare del Golfo to Oudewater | 1,041.34 mi (1,675.87 km) |
