| Willoughby to Oerlinghausen | 4,040.50 mi (6,502.56 km) |
| Willoughby to Oestrich-Winkel | 4,081.23 mi (6,568.10 km) |
| Willoughby to Offenburg | 4,131.25 mi (6,648.60 km) |
| Willoughby to Oftersheim | 4,125.49 mi (6,639.34 km) |
| Willoughby to Ohrdruf | 4,156.83 mi (6,689.77 km) |
| Willoughby to Ohringen | 4,167.04 mi (6,706.21 km) |
| Willoughby to Olbernhau | 4,259.68 mi (6,855.30 km) |
| Willoughby to Olching | 4,273.76 mi (6,877.95 km) |
| Willoughby to Oldenburg | 3,985.19 mi (6,413.55 km) |
| Willoughby to Oldenburg in Holstein | 4,043.28 mi (6,507.04 km) |
| Willoughby to Olfen | 4,000.56 mi (6,438.28 km) |
| Willoughby to Olpe | 4,040.67 mi (6,502.83 km) |
| Willoughby to Olsberg | 4,054.20 mi (6,524.60 km) |
| Willoughby to Oranienburg | 4,180.41 mi (6,727.71 km) |
| Willoughby to Ortenberg | 4,109.67 mi (6,613.87 km) |
