| Idrija to Oerlinghausen | 478.13 mi (769.48 km) |
| Idrija to Oestrich-Winkel | 392.11 mi (631.04 km) |
| Idrija to Offenburg | 332.61 mi (535.29 km) |
| Idrija to Oftersheim | 343.71 mi (553.14 km) |
| Idrija to Ohrdruf | 365.96 mi (588.96 km) |
| Idrija to Ohringen | 305.34 mi (491.40 km) |
| Idrija to Olbernhau | 323.83 mi (521.16 km) |
| Idrija to Olching | 198.24 mi (319.03 km) |
| Idrija to Oldenburg | 557.52 mi (897.25 km) |
| Idrija to Oldenburg in Holstein | 589.80 mi (949.20 km) |
| Idrija to Olfen | 496.65 mi (799.29 km) |
| Idrija to Olpe | 447.35 mi (719.95 km) |
| Idrija to Olsberg | 447.48 mi (720.15 km) |
| Idrija to Oranienburg | 467.86 mi (752.94 km) |
| Idrija to Ortenberg | 377.90 mi (608.17 km) |
