| McKeesport to Oerlinghausen | 4,043.86 mi (6,507.96 km) |
| McKeesport to Oestrich-Winkel | 4,079.79 mi (6,565.78 km) |
| McKeesport to Offenburg | 4,126.44 mi (6,640.87 km) |
| McKeesport to Oftersheim | 4,123.14 mi (6,635.56 km) |
| McKeesport to Ohrdruf | 4,159.25 mi (6,693.66 km) |
| McKeesport to Ohringen | 4,165.04 mi (6,702.99 km) |
| McKeesport to Olbernhau | 4,263.78 mi (6,861.89 km) |
| McKeesport to Olching | 4,271.14 mi (6,873.73 km) |
| McKeesport to Oldenburg | 3,990.84 mi (6,422.64 km) |
| McKeesport to Oldenburg in Holstein | 4,053.30 mi (6,523.16 km) |
| McKeesport to Olfen | 4,002.45 mi (6,441.32 km) |
| McKeesport to Olpe | 4,041.33 mi (6,503.89 km) |
| McKeesport to Olsberg | 4,056.06 mi (6,527.60 km) |
| McKeesport to Oranienburg | 4,188.77 mi (6,741.18 km) |
| McKeesport to Ortenberg | 4,109.80 mi (6,614.08 km) |
