| Viterbo to Noventa Vicentina | 199.96 mi (321.81 km) |
| Viterbo to Novi di Modena | 181.26 mi (291.70 km) |
| Viterbo to Novi Ligure | 231.77 mi (373.00 km) |
| Viterbo to Nuoro | 204.27 mi (328.74 km) |
| Viterbo to Occhiobello | 174.90 mi (281.48 km) |
| Viterbo to Oderzo | 233.10 mi (375.14 km) |
| Viterbo to Oggiono | 269.63 mi (433.92 km) |
| Viterbo to Olbia | 169.79 mi (273.26 km) |
| Viterbo to Oleggio | 279.35 mi (449.57 km) |
| Viterbo to Olgiate Comasco | 279.73 mi (450.19 km) |
| Viterbo to Olgiate Olona | 273.70 mi (440.47 km) |
| Viterbo to Omegna | 301.15 mi (484.65 km) |
| Viterbo to Opera | 250.21 mi (402.67 km) |
| Viterbo to Oppeano | 204.30 mi (328.79 km) |
| Viterbo to Orbassano | 289.78 mi (466.36 km) |
