| Watertown Town to Olivares | 3,379.53 mi (5,438.83 km) |
| Watertown Town to Olivenza | 3,293.96 mi (5,301.11 km) |
| Watertown Town to Olot | 3,638.71 mi (5,855.94 km) |
| Watertown Town to Onate | 3,388.34 mi (5,453.00 km) |
| Watertown Town to Onda | 3,581.02 mi (5,763.09 km) |
| Watertown Town to Onteniente | 3,601.41 mi (5,795.91 km) |
| Watertown Town to Orihuela | 3,609.29 mi (5,808.59 km) |
| Watertown Town to Osuna | 3,436.55 mi (5,530.59 km) |
| Watertown Town to Ourense | 3,153.57 mi (5,075.18 km) |
| Watertown Town to Oviedo | 3,220.88 mi (5,183.50 km) |
| Watertown Town to Paiporta | 3,590.81 mi (5,778.85 km) |
| Watertown Town to Pajara | 3,293.68 mi (5,300.66 km) |
| Watertown Town to Palafolls | 3,666.85 mi (5,901.22 km) |
| Watertown Town to Palafrugell | 3,677.83 mi (5,918.90 km) |
| Watertown Town to Palamos | 3,678.55 mi (5,920.05 km) |
