| Havre de Grace to Octeville | 3,577.04 mi (5,756.69 km) |
| Havre de Grace to Oignies | 3,750.35 mi (6,035.60 km) |
| Havre de Grace to Oissel | 3,699.16 mi (5,953.22 km) |
| Havre de Grace to Olivet | 3,771.00 mi (6,068.85 km) |
| Havre de Grace to Ollioules | 4,081.03 mi (6,567.78 km) |
| Havre de Grace to Olonne-sur-Mer | 3,644.63 mi (5,865.47 km) |
| Havre de Grace to Oloron-Sainte-Marie | 3,785.99 mi (6,092.97 km) |
| Havre de Grace to Onet Village | 3,897.98 mi (6,273.19 km) |
| Havre de Grace to Onnaing | 3,777.17 mi (6,078.78 km) |
| Havre de Grace to Orange | 4,003.76 mi (6,443.44 km) |
| Havre de Grace to Orchies | 3,760.48 mi (6,051.91 km) |
| Havre de Grace to Orleans | 3,770.36 mi (6,067.80 km) |
| Havre de Grace to Orly | 3,769.10 mi (6,065.78 km) |
| Havre de Grace to Ormesson-sur-Marne | 3,774.16 mi (6,073.93 km) |
| Havre de Grace to Orsay | 3,761.60 mi (6,053.71 km) |
