| Harper Woods to Nuth | 3,990.93 mi (6,422.78 km) |
| Harper Woods to Oegstgeest | 3,895.69 mi (6,269.51 km) |
| Harper Woods to Oirschot | 3,949.33 mi (6,355.84 km) |
| Harper Woods to Oisterwijk | 3,942.81 mi (6,345.34 km) |
| Harper Woods to Oldebroek | 3,940.44 mi (6,341.53 km) |
| Harper Woods to Oldenzaal | 3,983.07 mi (6,410.13 km) |
| Harper Woods to Ommen | 3,957.33 mi (6,368.71 km) |
| Harper Woods to Oosterend | 3,928.43 mi (6,322.19 km) |
| Harper Woods to Oosterhout | 3,927.89 mi (6,321.33 km) |
| Harper Woods to Oosterwolde | 3,937.10 mi (6,336.16 km) |
| Harper Woods to Oostzaan | 3,903.22 mi (6,281.62 km) |
| Harper Woods to Opmeer | 3,897.11 mi (6,271.80 km) |
| Harper Woods to Oss | 3,948.67 mi (6,354.78 km) |
| Harper Woods to Oud-Beijerland | 3,905.00 mi (6,284.48 km) |
| Harper Woods to Oudenbosch | 3,917.06 mi (6,303.89 km) |
