| Delaware to Olivares | 4,007.28 mi (6,449.09 km) |
| Delaware to Olivenza | 3,920.18 mi (6,308.93 km) |
| Delaware to Olot | 4,245.85 mi (6,833.04 km) |
| Delaware to Onate | 3,998.77 mi (6,435.40 km) |
| Delaware to Onda | 4,198.09 mi (6,756.17 km) |
| Delaware to Onteniente | 4,221.67 mi (6,794.12 km) |
| Delaware to Orihuela | 4,231.53 mi (6,809.99 km) |
| Delaware to Osuna | 4,063.86 mi (6,540.16 km) |
| Delaware to Ourense | 3,771.87 mi (6,070.25 km) |
| Delaware to Oviedo | 3,834.04 mi (6,170.30 km) |
| Delaware to Paiporta | 4,209.41 mi (6,774.40 km) |
| Delaware to Pajara | 3,922.86 mi (6,313.23 km) |
| Delaware to Palafolls | 4,275.31 mi (6,880.44 km) |
| Delaware to Palafrugell | 4,284.95 mi (6,895.95 km) |
| Delaware to Palamos | 4,285.94 mi (6,897.55 km) |
