| Romanshorn to Olivares | 1,052.70 mi (1,694.15 km) |
| Romanshorn to Olivenza | 1,028.49 mi (1,655.19 km) |
| Romanshorn to Olot | 500.92 mi (806.15 km) |
| Romanshorn to Onate | 651.23 mi (1,048.05 km) |
| Romanshorn to Onda | 710.44 mi (1,143.35 km) |
| Romanshorn to Onteniente | 783.96 mi (1,261.66 km) |
| Romanshorn to Orihuela | 836.00 mi (1,345.41 km) |
| Romanshorn to Osuna | 1,023.24 mi (1,646.75 km) |
| Romanshorn to Ourense | 913.68 mi (1,470.42 km) |
| Romanshorn to Oviedo | 790.21 mi (1,271.71 km) |
| Romanshorn to Paiporta | 744.47 mi (1,198.11 km) |
| Romanshorn to Pajara | 1,828.39 mi (2,942.50 km) |
| Romanshorn to Palafolls | 520.57 mi (837.77 km) |
| Romanshorn to Palafrugell | 494.20 mi (795.33 km) |
| Romanshorn to Palamos | 499.24 mi (803.45 km) |
