| Key West to Oerlinghausen | 4,915.98 mi (7,911.51 km) |
| Key West to Oestrich-Winkel | 4,925.89 mi (7,927.45 km) |
| Key West to Offenburg | 4,952.98 mi (7,971.06 km) |
| Key West to Oftersheim | 4,963.31 mi (7,987.68 km) |
| Key West to Ohrdruf | 5,024.13 mi (8,085.56 km) |
| Key West to Ohringen | 5,006.20 mi (8,056.71 km) |
| Key West to Olbernhau | 5,135.32 mi (8,264.50 km) |
| Key West to Olching | 5,106.54 mi (8,218.18 km) |
| Key West to Oldenburg | 4,875.67 mi (7,846.64 km) |
| Key West to Oldenburg in Holstein | 4,958.31 mi (7,979.63 km) |
| Key West to Olfen | 4,867.88 mi (7,834.09 km) |
| Key West to Olpe | 4,899.49 mi (7,884.97 km) |
| Key West to Olsberg | 4,920.24 mi (7,918.36 km) |
| Key West to Oranienburg | 5,083.32 mi (8,180.81 km) |
| Key West to Ortenberg | 4,963.66 mi (7,988.23 km) |
