| Cay to Oerlinghausen | 1,416.43 mi (2,279.52 km) |
| Cay to Oestrich-Winkel | 1,375.83 mi (2,214.18 km) |
| Cay to Offenburg | 1,335.24 mi (2,148.86 km) |
| Cay to Oftersheim | 1,333.37 mi (2,145.85 km) |
| Cay to Ohrdruf | 1,299.11 mi (2,090.71 km) |
| Cay to Ohringen | 1,291.12 mi (2,077.85 km) |
| Cay to Olbernhau | 1,199.55 mi (1,930.50 km) |
| Cay to Olching | 1,186.10 mi (1,908.85 km) |
| Cay to Oldenburg | 1,476.50 mi (2,376.20 km) |
| Cay to Oldenburg in Holstein | 1,437.90 mi (2,314.08 km) |
| Cay to Olfen | 1,454.82 mi (2,341.30 km) |
| Cay to Olpe | 1,414.51 mi (2,276.43 km) |
| Cay to Olsberg | 1,401.20 mi (2,255.01 km) |
| Cay to Oranienburg | 1,294.79 mi (2,083.77 km) |
| Cay to Ortenberg | 1,345.70 mi (2,165.70 km) |
