| Roskilde to Oria | 1,076.81 mi (1,732.96 km) |
| Roskilde to Oristano | 1,099.48 mi (1,769.44 km) |
| Roskilde to Orta Nova | 1,002.86 mi (1,613.95 km) |
| Roskilde to Orte | 911.42 mi (1,466.79 km) |
| Roskilde to Ortona | 924.79 mi (1,488.30 km) |
| Roskilde to Orvieto | 893.49 mi (1,437.94 km) |
| Roskilde to Orzinuovi | 714.38 mi (1,149.69 km) |
| Roskilde to Osimo | 842.93 mi (1,356.56 km) |
| Roskilde to Ospitaletto | 702.95 mi (1,131.28 km) |
| Roskilde to Ostuni | 1,060.49 mi (1,706.70 km) |
| Roskilde to Ottaviano | 1,028.34 mi (1,654.95 km) |
| Roskilde to Ovada | 775.60 mi (1,248.20 km) |
| Roskilde to Ozieri | 1,050.28 mi (1,690.27 km) |
| Roskilde to Paceco | 1,220.84 mi (1,964.76 km) |
| Roskilde to Pachino | 1,315.79 mi (2,117.56 km) |
