| Glenmont to Oerlinghausen | 3,996.83 mi (6,432.27 km) |
| Glenmont to Oestrich-Winkel | 4,026.14 mi (6,479.44 km) |
| Glenmont to Offenburg | 4,068.16 mi (6,547.07 km) |
| Glenmont to Oftersheim | 4,068.17 mi (6,547.08 km) |
| Glenmont to Ohrdruf | 4,110.69 mi (6,615.51 km) |
| Glenmont to Ohringen | 4,110.46 mi (6,615.15 km) |
| Glenmont to Olbernhau | 4,217.31 mi (6,787.11 km) |
| Glenmont to Olching | 4,215.51 mi (6,784.21 km) |
| Glenmont to Oldenburg | 3,947.08 mi (6,352.22 km) |
| Glenmont to Oldenburg in Holstein | 4,015.46 mi (6,462.26 km) |
| Glenmont to Olfen | 3,953.50 mi (6,362.54 km) |
| Glenmont to Olpe | 3,990.62 mi (6,422.28 km) |
| Glenmont to Olsberg | 4,006.97 mi (6,448.59 km) |
| Glenmont to Oranienburg | 4,148.35 mi (6,676.13 km) |
| Glenmont to Ortenberg | 4,058.22 mi (6,531.07 km) |
