| Barrhead to Olivares | 1,272.88 mi (2,048.50 km) |
| Barrhead to Olivenza | 1,189.14 mi (1,913.73 km) |
| Barrhead to Olot | 990.10 mi (1,593.42 km) |
| Barrhead to Onate | 886.51 mi (1,426.70 km) |
| Barrhead to Onda | 1,110.41 mi (1,787.03 km) |
| Barrhead to Onteniente | 1,185.98 mi (1,908.65 km) |
| Barrhead to Orihuela | 1,234.36 mi (1,986.50 km) |
| Barrhead to Osuna | 1,283.33 mi (2,065.32 km) |
| Barrhead to Ourense | 943.21 mi (1,517.95 km) |
| Barrhead to Oviedo | 862.01 mi (1,387.27 km) |
| Barrhead to Paiporta | 1,145.82 mi (1,844.02 km) |
| Barrhead to Pajara | 1,956.67 mi (3,148.96 km) |
| Barrhead to Palafolls | 1,027.87 mi (1,654.20 km) |
| Barrhead to Palafrugell | 1,017.39 mi (1,637.34 km) |
| Barrhead to Palamos | 1,021.62 mi (1,644.14 km) |
