| Willoughby to Nuth | 3,969.18 mi (6,387.77 km) |
| Willoughby to Oegstgeest | 3,875.32 mi (6,236.72 km) |
| Willoughby to Oirschot | 3,928.24 mi (6,321.89 km) |
| Willoughby to Oisterwijk | 3,921.80 mi (6,311.53 km) |
| Willoughby to Oldebroek | 3,921.31 mi (6,310.74 km) |
| Willoughby to Oldenzaal | 3,964.29 mi (6,379.91 km) |
| Willoughby to Ommen | 3,938.61 mi (6,338.57 km) |
| Willoughby to Oosterend | 3,910.35 mi (6,293.10 km) |
| Willoughby to Oosterhout | 3,906.80 mi (6,287.38 km) |
| Willoughby to Oosterwolde | 3,919.12 mi (6,307.22 km) |
| Willoughby to Oostzaan | 3,883.51 mi (6,249.90 km) |
| Willoughby to Opmeer | 3,877.90 mi (6,240.88 km) |
| Willoughby to Oss | 3,928.16 mi (6,321.76 km) |
| Willoughby to Oud-Beijerland | 3,883.95 mi (6,250.61 km) |
| Willoughby to Oudenbosch | 3,895.68 mi (6,269.50 km) |
