| Clayton to Noventa Vicentina | 835.89 mi (1,345.23 km) |
| Clayton to Novi di Modena | 837.10 mi (1,347.18 km) |
| Clayton to Novi Ligure | 783.72 mi (1,261.27 km) |
| Clayton to Nuoro | 1,065.28 mi (1,714.40 km) |
| Clayton to Occhiobello | 856.51 mi (1,378.42 km) |
| Clayton to Oderzo | 841.62 mi (1,354.45 km) |
| Clayton to Oggiono | 742.24 mi (1,194.51 km) |
| Clayton to Olbia | 1,031.89 mi (1,660.66 km) |
| Clayton to Oleggio | 731.68 mi (1,177.52 km) |
| Clayton to Olgiate Comasco | 731.01 mi (1,176.45 km) |
| Clayton to Olgiate Olona | 736.92 mi (1,185.96 km) |
| Clayton to Omegna | 709.71 mi (1,142.17 km) |
| Clayton to Opera | 760.40 mi (1,223.74 km) |
| Clayton to Oppeano | 824.00 mi (1,326.11 km) |
| Clayton to Orbassano | 736.47 mi (1,185.23 km) |
