| Merrillville to Octeville | 3,954.86 mi (6,364.73 km) |
| Merrillville to Oignies | 4,108.08 mi (6,611.31 km) |
| Merrillville to Oissel | 4,072.35 mi (6,553.81 km) |
| Merrillville to Olivet | 4,154.98 mi (6,686.80 km) |
| Merrillville to Ollioules | 4,490.97 mi (7,227.52 km) |
| Merrillville to Olonne-sur-Mer | 4,050.32 mi (6,518.36 km) |
| Merrillville to Oloron-Sainte-Marie | 4,215.53 mi (6,784.24 km) |
| Merrillville to Onet Village | 4,308.77 mi (6,934.30 km) |
| Merrillville to Onnaing | 4,133.97 mi (6,652.98 km) |
| Merrillville to Orange | 4,409.43 mi (7,096.29 km) |
| Merrillville to Orchies | 4,117.47 mi (6,626.42 km) |
| Merrillville to Orleans | 4,153.98 mi (6,685.18 km) |
| Merrillville to Orly | 4,144.00 mi (6,669.12 km) |
| Merrillville to Ormesson-sur-Marne | 4,148.28 mi (6,676.01 km) |
| Merrillville to Orsay | 4,137.48 mi (6,658.63 km) |
