| Williamstown to Olivares | 3,627.42 mi (5,837.77 km) |
| Williamstown to Olivenza | 3,543.86 mi (5,703.29 km) |
| Williamstown to Olot | 3,900.86 mi (6,277.83 km) |
| Williamstown to Onate | 3,649.30 mi (5,872.99 km) |
| Williamstown to Onda | 3,838.28 mi (6,177.12 km) |
| Williamstown to Onteniente | 3,856.48 mi (6,206.41 km) |
| Williamstown to Orihuela | 3,862.78 mi (6,216.54 km) |
| Williamstown to Osuna | 3,684.95 mi (5,930.35 km) |
| Williamstown to Ourense | 3,410.48 mi (5,488.64 km) |
| Williamstown to Oviedo | 3,480.70 mi (5,601.64 km) |
| Williamstown to Paiporta | 3,847.07 mi (6,191.26 km) |
| Williamstown to Pajara | 3,505.84 mi (5,642.11 km) |
| Williamstown to Palafolls | 3,928.43 mi (6,322.20 km) |
| Williamstown to Palafrugell | 3,939.96 mi (6,340.76 km) |
| Williamstown to Palamos | 3,940.56 mi (6,341.73 km) |
