| Champaign to Oerlinghausen | 4,368.11 mi (7,029.80 km) |
| Champaign to Oestrich-Winkel | 4,415.44 mi (7,105.96 km) |
| Champaign to Offenburg | 4,469.77 mi (7,193.39 km) |
| Champaign to Oftersheim | 4,460.84 mi (7,179.03 km) |
| Champaign to Ohrdruf | 4,485.53 mi (7,218.76 km) |
| Champaign to Ohringen | 4,501.84 mi (7,245.01 km) |
| Champaign to Olbernhau | 4,585.71 mi (7,379.99 km) |
| Champaign to Olching | 4,609.17 mi (7,417.74 km) |
| Champaign to Oldenburg | 4,309.55 mi (6,935.55 km) |
| Champaign to Oldenburg in Holstein | 4,360.76 mi (7,017.96 km) |
| Champaign to Olfen | 4,330.35 mi (6,969.03 km) |
| Champaign to Olpe | 4,372.09 mi (7,036.20 km) |
| Champaign to Olsberg | 4,383.90 mi (7,055.21 km) |
| Champaign to Oranienburg | 4,500.13 mi (7,242.26 km) |
| Champaign to Ortenberg | 4,441.68 mi (7,148.19 km) |
