| Oro Valley to Oerlinghausen | 5,561.99 mi (8,951.17 km) |
| Oro Valley to Oestrich-Winkel | 5,630.99 mi (9,062.20 km) |
| Oro Valley to Offenburg | 5,699.30 mi (9,172.13 km) |
| Oro Valley to Oftersheim | 5,679.50 mi (9,140.27 km) |
| Oro Valley to Ohrdruf | 5,680.79 mi (9,142.35 km) |
| Oro Valley to Ohringen | 5,717.87 mi (9,202.03 km) |
| Oro Valley to Olbernhau | 5,769.70 mi (9,285.44 km) |
| Oro Valley to Olching | 5,825.52 mi (9,375.27 km) |
| Oro Valley to Oldenburg | 5,493.69 mi (8,841.23 km) |
| Oro Valley to Oldenburg in Holstein | 5,520.52 mi (8,884.42 km) |
| Oro Valley to Olfen | 5,532.40 mi (8,903.54 km) |
| Oro Valley to Olpe | 5,578.89 mi (8,978.36 km) |
| Oro Valley to Olsberg | 5,584.61 mi (8,987.56 km) |
| Oro Valley to Oranienburg | 5,664.26 mi (9,115.75 km) |
| Oro Valley to Ortenberg | 5,649.20 mi (9,091.51 km) |
