| Casper to Octeville | 4,599.27 mi (7,401.81 km) |
| Casper to Oignies | 4,717.59 mi (7,592.22 km) |
| Casper to Oissel | 4,705.71 mi (7,573.11 km) |
| Casper to Olivet | 4,801.08 mi (7,726.59 km) |
| Casper to Ollioules | 5,164.54 mi (8,311.53 km) |
| Casper to Olonne-sur-Mer | 4,731.47 mi (7,614.56 km) |
| Casper to Oloron-Sainte-Marie | 4,926.20 mi (7,927.95 km) |
| Casper to Onet Village | 4,989.15 mi (8,029.26 km) |
| Casper to Onnaing | 4,741.11 mi (7,630.08 km) |
| Casper to Orange | 5,079.10 mi (8,174.02 km) |
| Casper to Orchies | 4,725.53 mi (7,605.01 km) |
| Casper to Orleans | 4,799.58 mi (7,724.18 km) |
| Casper to Orly | 4,777.23 mi (7,688.20 km) |
| Casper to Ormesson-sur-Marne | 4,780.21 mi (7,693.00 km) |
| Casper to Orsay | 4,772.38 mi (7,680.40 km) |
