| Glenn Dale to Olivares | 3,736.03 mi (6,012.56 km) |
| Glenn Dale to Olivenza | 3,652.62 mi (5,878.33 km) |
| Glenn Dale to Olot | 4,009.62 mi (6,452.86 km) |
| Glenn Dale to Onate | 3,758.16 mi (6,048.18 km) |
| Glenn Dale to Onda | 3,947.28 mi (6,352.54 km) |
| Glenn Dale to Onteniente | 3,965.47 mi (6,381.80 km) |
| Glenn Dale to Orihuela | 3,971.72 mi (6,391.86 km) |
| Glenn Dale to Osuna | 3,793.60 mi (6,105.21 km) |
| Glenn Dale to Ourense | 3,519.49 mi (5,664.07 km) |
| Glenn Dale to Oviedo | 3,589.62 mi (5,776.94 km) |
| Glenn Dale to Paiporta | 3,956.07 mi (6,366.68 km) |
| Glenn Dale to Pajara | 3,608.97 mi (5,808.07 km) |
| Glenn Dale to Palafolls | 4,037.25 mi (6,497.32 km) |
| Glenn Dale to Palafrugell | 4,048.73 mi (6,515.80 km) |
| Glenn Dale to Palamos | 4,049.34 mi (6,516.78 km) |
