| South Milwaukee to Oberkirch | 4,326.28 mi (6,962.47 km) |
| South Milwaukee to Obernburg am Main | 4,313.82 mi (6,942.43 km) |
| South Milwaukee to Obernkirchen | 4,218.33 mi (6,788.74 km) |
| South Milwaukee to Oberschleissheim | 4,467.21 mi (7,189.28 km) |
| South Milwaukee to Oberstdorf | 4,454.06 mi (7,168.12 km) |
| South Milwaukee to Obertraubling | 4,459.39 mi (7,176.70 km) |
| South Milwaukee to Obertshausen | 4,293.64 mi (6,909.95 km) |
| South Milwaukee to Oberursel | 4,278.94 mi (6,886.28 km) |
| South Milwaukee to Ochsenfurt | 4,355.15 mi (7,008.93 km) |
| South Milwaukee to Ochsenhausen | 4,414.56 mi (7,104.55 km) |
| South Milwaukee to Ochtrup | 4,152.43 mi (6,682.69 km) |
| South Milwaukee to Odenthal | 4,193.84 mi (6,749.33 km) |
| South Milwaukee to Oelde | 4,200.66 mi (6,760.31 km) |
| South Milwaukee to Oelsnitz | 4,399.46 mi (7,080.25 km) |
| South Milwaukee to Oer-Erkenschwick | 4,175.71 mi (6,720.15 km) |
