| Pikesville to Oberkirch | 4,044.11 mi (6,508.37 km) |
| Pikesville to Obernburg am Main | 4,048.41 mi (6,515.29 km) |
| Pikesville to Obernkirchen | 3,977.33 mi (6,400.89 km) |
| Pikesville to Oberschleissheim | 4,195.76 mi (6,752.43 km) |
| Pikesville to Oberstdorf | 4,169.63 mi (6,710.37 km) |
| Pikesville to Obertraubling | 4,197.08 mi (6,754.55 km) |
| Pikesville to Obertshausen | 4,029.34 mi (6,484.59 km) |
| Pikesville to Oberursel | 4,015.06 mi (6,461.61 km) |
| Pikesville to Ochsenfurt | 4,091.32 mi (6,584.35 km) |
| Pikesville to Ochsenhausen | 4,135.08 mi (6,654.76 km) |
| Pikesville to Ochtrup | 3,904.17 mi (6,283.16 km) |
| Pikesville to Odenthal | 3,933.16 mi (6,329.82 km) |
| Pikesville to Oelde | 3,951.82 mi (6,359.84 km) |
| Pikesville to Oelsnitz | 4,151.09 mi (6,680.54 km) |
| Pikesville to Oer-Erkenschwick | 3,921.78 mi (6,311.50 km) |
