| Willoughby to Oberkirch | 4,134.87 mi (6,654.43 km) |
| Willoughby to Obernburg am Main | 4,130.79 mi (6,647.86 km) |
| Willoughby to Obernkirchen | 4,047.29 mi (6,513.49 km) |
| Willoughby to Oberschleissheim | 4,281.65 mi (6,890.65 km) |
| Willoughby to Oberstdorf | 4,261.93 mi (6,858.92 km) |
| Willoughby to Obertraubling | 4,278.41 mi (6,885.44 km) |
| Willoughby to Obertshausen | 4,111.09 mi (6,616.17 km) |
| Willoughby to Oberursel | 4,096.55 mi (6,592.76 km) |
| Willoughby to Ochsenfurt | 4,173.05 mi (6,715.88 km) |
| Willoughby to Ochsenhausen | 4,224.79 mi (6,799.14 km) |
| Willoughby to Ochtrup | 3,977.48 mi (6,401.13 km) |
| Willoughby to Odenthal | 4,012.77 mi (6,457.92 km) |
| Willoughby to Oelde | 4,025.59 mi (6,478.56 km) |
| Willoughby to Oelsnitz | 4,225.33 mi (6,800.01 km) |
| Willoughby to Oer-Erkenschwick | 3,997.98 mi (6,434.12 km) |
