| Harrisburg to Oerlinghausen | 3,933.55 mi (6,330.43 km) |
| Harrisburg to Oestrich-Winkel | 3,965.13 mi (6,381.27 km) |
| Harrisburg to Offenburg | 4,008.83 mi (6,451.59 km) |
| Harrisburg to Oftersheim | 4,007.65 mi (6,449.68 km) |
| Harrisburg to Ohrdruf | 4,047.95 mi (6,514.55 km) |
| Harrisburg to Ohringen | 4,049.81 mi (6,517.54 km) |
| Harrisburg to Olbernhau | 4,153.90 mi (6,685.06 km) |
| Harrisburg to Olching | 4,155.26 mi (6,687.25 km) |
| Harrisburg to Oldenburg | 3,882.72 mi (6,248.63 km) |
| Harrisburg to Oldenburg in Holstein | 3,949.25 mi (6,355.70 km) |
| Harrisburg to Olfen | 3,890.85 mi (6,261.72 km) |
| Harrisburg to Olpe | 3,928.58 mi (6,322.44 km) |
| Harrisburg to Olsberg | 3,944.38 mi (6,347.87 km) |
| Harrisburg to Oranienburg | 4,082.98 mi (6,570.91 km) |
| Harrisburg to Ortenberg | 3,996.50 mi (6,431.74 km) |
