| Calhoun to Nuth | 4,449.51 mi (7,160.80 km) |
| Calhoun to Oegstgeest | 4,359.10 mi (7,015.29 km) |
| Calhoun to Oirschot | 4,410.22 mi (7,097.57 km) |
| Calhoun to Oisterwijk | 4,404.00 mi (7,087.56 km) |
| Calhoun to Oldebroek | 4,407.72 mi (7,093.53 km) |
| Calhoun to Oldenzaal | 4,451.33 mi (7,163.72 km) |
| Calhoun to Ommen | 4,425.83 mi (7,122.68 km) |
| Calhoun to Oosterend | 4,399.04 mi (7,079.57 km) |
| Calhoun to Oosterhout | 4,388.84 mi (7,063.16 km) |
| Calhoun to Oosterwolde | 4,408.00 mi (7,093.99 km) |
| Calhoun to Oostzaan | 4,368.73 mi (7,030.80 km) |
| Calhoun to Opmeer | 4,364.25 mi (7,023.58 km) |
| Calhoun to Oss | 4,411.46 mi (7,099.56 km) |
| Calhoun to Oud-Beijerland | 4,366.17 mi (7,026.67 km) |
| Calhoun to Oudenbosch | 4,377.12 mi (7,044.30 km) |
