| Viterbo to Oerlinghausen | 678.96 mi (1,092.68 km) |
| Viterbo to Oestrich-Winkel | 559.15 mi (899.87 km) |
| Viterbo to Offenburg | 464.05 mi (746.82 km) |
| Viterbo to Oftersheim | 509.13 mi (819.37 km) |
| Viterbo to Ohrdruf | 584.64 mi (940.89 km) |
| Viterbo to Ohringen | 484.96 mi (780.48 km) |
| Viterbo to Olbernhau | 572.85 mi (921.92 km) |
| Viterbo to Olching | 401.28 mi (645.80 km) |
| Viterbo to Oldenburg | 762.45 mi (1,227.04 km) |
| Viterbo to Oldenburg in Holstein | 822.80 mi (1,324.17 km) |
| Viterbo to Olfen | 679.40 mi (1,093.39 km) |
| Viterbo to Olpe | 627.30 mi (1,009.54 km) |
| Viterbo to Olsberg | 640.14 mi (1,030.21 km) |
| Viterbo to Oranienburg | 716.06 mi (1,152.38 km) |
| Viterbo to Ortenberg | 567.20 mi (912.82 km) |
