| South Houston to Oerlinghausen | 5,172.18 mi (8,323.82 km) |
| South Houston to Oestrich-Winkel | 5,212.89 mi (8,389.34 km) |
| South Houston to Offenburg | 5,261.99 mi (8,468.36 km) |
| South Houston to Oftersheim | 5,256.99 mi (8,460.31 km) |
| South Houston to Ohrdruf | 5,288.62 mi (8,511.21 km) |
| South Houston to Ohringen | 5,298.62 mi (8,527.30 km) |
| South Houston to Olbernhau | 5,391.19 mi (8,676.28 km) |
| South Houston to Olching | 5,405.21 mi (8,698.84 km) |
| South Houston to Oldenburg | 5,116.35 mi (8,233.97 km) |
| South Houston to Oldenburg in Holstein | 5,172.42 mi (8,324.21 km) |
| South Houston to Olfen | 5,132.40 mi (8,259.79 km) |
| South Houston to Olpe | 5,172.53 mi (8,324.38 km) |
| South Houston to Olsberg | 5,186.03 mi (8,346.11 km) |
| South Houston to Oranienburg | 5,310.39 mi (8,546.24 km) |
| South Houston to Ortenberg | 5,241.50 mi (8,435.39 km) |
