| Tulcea to Octeville | 1,445.60 mi (2,326.47 km) |
| Tulcea to Oignies | 1,244.12 mi (2,002.22 km) |
| Tulcea to Oissel | 1,322.47 mi (2,128.30 km) |
| Tulcea to Olivet | 1,285.32 mi (2,068.53 km) |
| Tulcea to Ollioules | 1,142.50 mi (1,838.68 km) |
| Tulcea to Olonne-sur-Mer | 1,464.72 mi (2,357.25 km) |
| Tulcea to Oloron-Sainte-Marie | 1,455.22 mi (2,341.95 km) |
| Tulcea to Onet Village | 1,280.92 mi (2,061.44 km) |
| Tulcea to Onnaing | 1,217.02 mi (1,958.60 km) |
| Tulcea to Orange | 1,176.82 mi (1,893.91 km) |
| Tulcea to Orchies | 1,233.23 mi (1,984.70 km) |
| Tulcea to Orleans | 1,284.85 mi (2,067.77 km) |
| Tulcea to Orly | 1,262.40 mi (2,031.64 km) |
| Tulcea to Ormesson-sur-Marne | 1,255.84 mi (2,021.09 km) |
| Tulcea to Orsay | 1,271.70 mi (2,046.60 km) |
