| McHenry to Orbetello | 4,741.81 mi (7,631.20 km) |
| McHenry to Oria | 5,081.82 mi (8,178.41 km) |
| McHenry to Oristano | 4,743.08 mi (7,633.25 km) |
| McHenry to Orta Nova | 4,968.68 mi (7,996.31 km) |
| McHenry to Orte | 4,787.56 mi (7,704.83 km) |
| McHenry to Ortona | 4,871.60 mi (7,840.09 km) |
| McHenry to Orvieto | 4,765.44 mi (7,669.23 km) |
| McHenry to Orzinuovi | 4,566.41 mi (7,348.92 km) |
| McHenry to Osimo | 4,785.90 mi (7,702.16 km) |
| McHenry to Ospitaletto | 4,565.40 mi (7,347.30 km) |
| McHenry to Ostuni | 5,069.07 mi (8,157.87 km) |
| McHenry to Ottaviano | 4,941.71 mi (7,952.92 km) |
| McHenry to Ovada | 4,547.36 mi (7,318.26 km) |
| McHenry to Ozieri | 4,731.30 mi (7,614.30 km) |
| McHenry to Paceco | 4,991.85 mi (8,033.60 km) |
