| Grammichele to Oerlinghausen | 1,059.84 mi (1,705.65 km) |
| Grammichele to Oestrich-Winkel | 942.78 mi (1,517.25 km) |
| Grammichele to Offenburg | 847.55 mi (1,364.00 km) |
| Grammichele to Oftersheim | 892.59 mi (1,436.49 km) |
| Grammichele to Ohrdruf | 960.03 mi (1,545.01 km) |
| Grammichele to Ohringen | 867.04 mi (1,395.36 km) |
| Grammichele to Olbernhau | 931.66 mi (1,499.37 km) |
| Grammichele to Olching | 777.30 mi (1,250.94 km) |
| Grammichele to Oldenburg | 1,143.05 mi (1,839.56 km) |
| Grammichele to Oldenburg in Holstein | 1,193.84 mi (1,921.29 km) |
| Grammichele to Olfen | 1,062.61 mi (1,710.11 km) |
| Grammichele to Olpe | 1,010.50 mi (1,626.24 km) |
| Grammichele to Olsberg | 1,022.07 mi (1,644.86 km) |
| Grammichele to Oranienburg | 1,075.81 mi (1,731.35 km) |
| Grammichele to Ortenberg | 948.99 mi (1,527.26 km) |
