| Gahanna to Nuth | 4,100.80 mi (6,599.60 km) |
| Gahanna to Oegstgeest | 4,007.41 mi (6,449.30 km) |
| Gahanna to Oirschot | 4,060.09 mi (6,534.08 km) |
| Gahanna to Oisterwijk | 4,053.68 mi (6,523.76 km) |
| Gahanna to Oldebroek | 4,053.77 mi (6,523.92 km) |
| Gahanna to Oldenzaal | 4,096.84 mi (6,593.23 km) |
| Gahanna to Ommen | 4,071.18 mi (6,551.93 km) |
| Gahanna to Oosterend | 4,043.11 mi (6,506.76 km) |
| Gahanna to Oosterhout | 4,038.65 mi (6,499.57 km) |
| Gahanna to Oosterwolde | 4,051.91 mi (6,520.93 km) |
| Gahanna to Oostzaan | 4,015.80 mi (6,462.80 km) |
| Gahanna to Opmeer | 4,010.35 mi (6,454.03 km) |
| Gahanna to Oss | 4,060.19 mi (6,534.25 km) |
| Gahanna to Oud-Beijerland | 4,015.82 mi (6,462.83 km) |
| Gahanna to Oudenbosch | 4,027.44 mi (6,481.55 km) |
