| Geilenkirchen to Oria | 909.44 mi (1,463.61 km) |
| Geilenkirchen to Oristano | 773.36 mi (1,244.61 km) |
| Geilenkirchen to Orta Nova | 807.20 mi (1,299.06 km) |
| Geilenkirchen to Orte | 657.80 mi (1,058.63 km) |
| Geilenkirchen to Ortona | 712.13 mi (1,146.06 km) |
| Geilenkirchen to Orvieto | 635.77 mi (1,023.17 km) |
| Geilenkirchen to Orzinuovi | 422.62 mi (680.14 km) |
| Geilenkirchen to Osimo | 621.12 mi (999.59 km) |
| Geilenkirchen to Ospitaletto | 415.54 mi (668.75 km) |
| Geilenkirchen to Ostuni | 894.58 mi (1,439.69 km) |
| Geilenkirchen to Ottaviano | 804.99 mi (1,295.51 km) |
| Geilenkirchen to Ovada | 452.48 mi (728.19 km) |
| Geilenkirchen to Ozieri | 730.40 mi (1,175.47 km) |
| Geilenkirchen to Paceco | 950.44 mi (1,529.59 km) |
| Geilenkirchen to Pachino | 1,079.54 mi (1,737.35 km) |
