| Milwaukee to Orbetello | 4,697.71 mi (7,560.24 km) |
| Milwaukee to Oria | 5,036.86 mi (8,106.05 km) |
| Milwaukee to Oristano | 4,700.81 mi (7,565.23 km) |
| Milwaukee to Orta Nova | 4,923.89 mi (7,924.24 km) |
| Milwaukee to Orte | 4,743.16 mi (7,633.37 km) |
| Milwaukee to Ortona | 4,826.75 mi (7,767.90 km) |
| Milwaukee to Orvieto | 4,721.00 mi (7,597.72 km) |
| Milwaukee to Orzinuovi | 4,521.36 mi (7,276.43 km) |
| Milwaukee to Osimo | 4,740.82 mi (7,629.61 km) |
| Milwaukee to Ospitaletto | 4,520.26 mi (7,274.65 km) |
| Milwaukee to Ostuni | 5,024.03 mi (8,085.39 km) |
| Milwaukee to Ottaviano | 4,897.43 mi (7,881.66 km) |
| Milwaukee to Ovada | 4,502.93 mi (7,246.77 km) |
| Milwaukee to Ozieri | 4,688.61 mi (7,545.59 km) |
| Milwaukee to Paceco | 4,949.31 mi (7,965.14 km) |
