| Trecastagni to Oberkirch | 832.04 mi (1,339.03 km) |
| Trecastagni to Obernburg am Main | 894.42 mi (1,439.43 km) |
| Trecastagni to Obernkirchen | 1,052.50 mi (1,693.84 km) |
| Trecastagni to Oberschleissheim | 755.70 mi (1,216.18 km) |
| Trecastagni to Oberstdorf | 719.14 mi (1,157.35 km) |
| Trecastagni to Obertraubling | 797.58 mi (1,283.59 km) |
| Trecastagni to Obertshausen | 914.05 mi (1,471.02 km) |
| Trecastagni to Oberursel | 927.11 mi (1,492.03 km) |
| Trecastagni to Ochsenfurt | 867.94 mi (1,396.81 km) |
| Trecastagni to Ochsenhausen | 767.37 mi (1,234.96 km) |
| Trecastagni to Ochtrup | 1,077.91 mi (1,734.72 km) |
| Trecastagni to Odenthal | 1,005.74 mi (1,618.58 km) |
| Trecastagni to Oelde | 1,038.40 mi (1,671.15 km) |
| Trecastagni to Oelsnitz | 896.00 mi (1,441.98 km) |
| Trecastagni to Oer-Erkenschwick | 1,041.34 mi (1,675.88 km) |
