| Watertown Town to Oerlinghausen | 3,615.84 mi (5,819.14 km) |
| Watertown Town to Oestrich-Winkel | 3,644.04 mi (5,864.52 km) |
| Watertown Town to Offenburg | 3,685.68 mi (5,931.53 km) |
| Watertown Town to Oftersheim | 3,685.93 mi (5,931.93 km) |
| Watertown Town to Ohrdruf | 3,729.36 mi (6,001.83 km) |
| Watertown Town to Ohringen | 3,728.26 mi (6,000.05 km) |
| Watertown Town to Olbernhau | 3,836.39 mi (6,174.07 km) |
| Watertown Town to Olching | 3,833.20 mi (6,168.94 km) |
| Watertown Town to Oldenburg | 3,566.91 mi (5,740.38 km) |
| Watertown Town to Oldenburg in Holstein | 3,637.05 mi (5,853.27 km) |
| Watertown Town to Olfen | 3,572.14 mi (5,748.80 km) |
| Watertown Town to Olpe | 3,608.94 mi (5,808.03 km) |
| Watertown Town to Olsberg | 3,625.57 mi (5,834.79 km) |
| Watertown Town to Oranienburg | 3,769.04 mi (6,065.68 km) |
| Watertown Town to Ortenberg | 3,676.39 mi (5,916.58 km) |
