| Williamsport to Oskaloosa (Iowa) | 809.27 mi (1,302.39 km) |
| Williamsport to Oswego (Illinois) | 585.49 mi (942.25 km) |
| Williamsport to Oswego (New York) | 155.25 mi (249.85 km) |
| Williamsport to Otsego (Minnesota) | 877.76 mi (1,412.61 km) |
| Williamsport to Ottawa (Illinois) | 611.54 mi (984.18 km) |
| Williamsport to Ottawa (Kansas) | 981.00 mi (1,578.77 km) |
| Williamsport to Ottumwa (Iowa) | 799.60 mi (1,286.83 km) |
| Williamsport to Overland (Missouri) | 726.69 mi (1,169.50 km) |
| Williamsport to Overland Park (Kansas) | 945.66 mi (1,521.89 km) |
| Williamsport to Overlea (Maryland) | 132.46 mi (213.17 km) |
| Williamsport to Oviedo (Florida) | 900.23 mi (1,448.78 km) |
| Williamsport to Owasso (Oklahoma) | 1,066.19 mi (1,715.87 km) |
| Williamsport to Owatonna (Minnesota) | 844.50 mi (1,359.08 km) |
| Williamsport to Owensboro (Kentucky) | 588.34 mi (946.85 km) |
| Williamsport to Owings Mills (Maryland) | 126.99 mi (204.37 km) |
