| Marshalltown to Oerlinghausen | 4,434.24 mi (7,136.22 km) |
| Marshalltown to Oestrich-Winkel | 4,491.19 mi (7,227.87 km) |
| Marshalltown to Offenburg | 4,552.06 mi (7,325.84 km) |
| Marshalltown to Oftersheim | 4,538.14 mi (7,303.43 km) |
| Marshalltown to Ohrdruf | 4,552.69 mi (7,326.85 km) |
| Marshalltown to Ohringen | 4,578.10 mi (7,367.74 km) |
| Marshalltown to Olbernhau | 4,648.55 mi (7,481.11 km) |
| Marshalltown to Olching | 4,685.93 mi (7,541.27 km) |
| Marshalltown to Oldenburg | 4,371.34 mi (7,034.99 km) |
| Marshalltown to Oldenburg in Holstein | 4,412.86 mi (7,101.81 km) |
| Marshalltown to Olfen | 4,399.85 mi (7,080.87 km) |
| Marshalltown to Olpe | 4,443.81 mi (7,151.63 km) |
| Marshalltown to Olsberg | 4,453.02 mi (7,166.44 km) |
| Marshalltown to Oranienburg | 4,554.58 mi (7,329.89 km) |
| Marshalltown to Ortenberg | 4,513.97 mi (7,264.53 km) |
