| Boulder City to Opwijk | 5,395.09 mi (8,682.56 km) |
| Boulder City to Ostend | 5,342.85 mi (8,598.48 km) |
| Boulder City to Oud-Heverlee | 5,416.67 mi (8,717.29 km) |
| Boulder City to Oud-Turnhout | 5,403.33 mi (8,695.82 km) |
| Boulder City to Oudenaarde | 5,382.18 mi (8,661.78 km) |
| Boulder City to Oudenburg | 5,347.40 mi (8,605.81 km) |
| Boulder City to Oupeye | 5,453.23 mi (8,776.13 km) |
| Boulder City to Overijse | 5,414.88 mi (8,714.40 km) |
| Boulder City to Overpelt | 5,421.57 mi (8,725.17 km) |
| Boulder City to Paal | 5,422.58 mi (8,726.80 km) |
| Boulder City to Peer | 5,426.77 mi (8,733.54 km) |
| Boulder City to Pepinster | 5,465.52 mi (8,795.91 km) |
| Boulder City to Peruwelz | 5,397.43 mi (8,686.33 km) |
| Boulder City to Perwez | 5,431.38 mi (8,740.97 km) |
| Boulder City to Philippeville | 5,443.37 mi (8,760.26 km) |
