| Baltimore to Octeville | 3,608.41 mi (5,807.18 km) |
| Baltimore to Oignies | 3,781.58 mi (6,085.87 km) |
| Baltimore to Oissel | 3,730.51 mi (6,003.68 km) |
| Baltimore to Olivet | 3,802.43 mi (6,119.42 km) |
| Baltimore to Ollioules | 4,112.54 mi (6,618.50 km) |
| Baltimore to Olonne-sur-Mer | 3,676.13 mi (5,916.16 km) |
| Baltimore to Oloron-Sainte-Marie | 3,817.49 mi (6,143.66 km) |
| Baltimore to Onet Village | 3,929.49 mi (6,323.90 km) |
| Baltimore to Onnaing | 3,808.41 mi (6,129.04 km) |
| Baltimore to Orange | 4,035.27 mi (6,494.14 km) |
| Baltimore to Orchies | 3,791.71 mi (6,102.17 km) |
| Baltimore to Orleans | 3,801.78 mi (6,118.37 km) |
| Baltimore to Orly | 3,800.47 mi (6,116.27 km) |
| Baltimore to Ormesson-sur-Marne | 3,805.53 mi (6,124.41 km) |
| Baltimore to Orsay | 3,792.97 mi (6,104.20 km) |
