| Harlingen to Olivenza | 1,164.31 mi (1,873.77 km) |
| Harlingen to Olot | 771.46 mi (1,241.55 km) |
| Harlingen to Onate | 787.48 mi (1,267.33 km) |
| Harlingen to Onda | 951.23 mi (1,530.86 km) |
| Harlingen to Onteniente | 1,032.10 mi (1,661.01 km) |
| Harlingen to Orihuela | 1,085.95 mi (1,747.67 km) |
| Harlingen to Osuna | 1,211.78 mi (1,950.17 km) |
| Harlingen to Ourense | 967.26 mi (1,556.65 km) |
| Harlingen to Oviedo | 851.42 mi (1,370.23 km) |
| Harlingen to Paiporta | 989.05 mi (1,591.73 km) |
| Harlingen to Pajara | 1,982.00 mi (3,189.73 km) |
| Harlingen to Palafolls | 804.52 mi (1,294.74 km) |
| Harlingen to Palafrugell | 784.76 mi (1,262.95 km) |
| Harlingen to Palamos | 789.88 mi (1,271.19 km) |
| Harlingen to Palencia | 897.88 mi (1,445.00 km) |
