| Madison to Oberkirch | 4,375.44 mi (7,041.59 km) |
| Madison to Obernburg am Main | 4,361.22 mi (7,018.70 km) |
| Madison to Obernkirchen | 4,263.25 mi (6,861.03 km) |
| Madison to Oberschleissheim | 4,515.01 mi (7,266.20 km) |
| Madison to Oberstdorf | 4,503.27 mi (7,247.31 km) |
| Madison to Obertraubling | 4,506.21 mi (7,252.05 km) |
| Madison to Obertshausen | 4,340.95 mi (6,986.08 km) |
| Madison to Oberursel | 4,326.22 mi (6,962.38 km) |
| Madison to Ochsenfurt | 4,402.30 mi (7,084.82 km) |
| Madison to Ochsenhausen | 4,463.30 mi (7,182.98 km) |
| Madison to Ochtrup | 4,198.25 mi (6,756.43 km) |
| Madison to Odenthal | 4,240.92 mi (6,825.10 km) |
| Madison to Oelde | 4,246.46 mi (6,834.02 km) |
| Madison to Oelsnitz | 4,444.88 mi (7,153.34 km) |
| Madison to Oer-Erkenschwick | 4,222.10 mi (6,794.81 km) |
