| Norristown to Oswego (Illinois) | 686.58 mi (1,104.94 km) |
| Norristown to Oswego (New York) | 237.66 mi (382.47 km) |
| Norristown to Otsego (Minnesota) | 991.28 mi (1,595.31 km) |
| Norristown to Ottawa (Illinois) | 710.41 mi (1,143.30 km) |
| Norristown to Ottawa (Kansas) | 1,067.27 mi (1,717.61 km) |
| Norristown to Ottumwa (Iowa) | 897.06 mi (1,443.67 km) |
| Norristown to Overland (Missouri) | 807.34 mi (1,299.30 km) |
| Norristown to Overland Park (Kansas) | 1,032.89 mi (1,662.27 km) |
| Norristown to Overlea (Maryland) | 81.61 mi (131.33 km) |
| Norristown to Oviedo (Florida) | 858.89 mi (1,382.24 km) |
| Norristown to Owasso (Oklahoma) | 1,140.86 mi (1,836.04 km) |
| Norristown to Owatonna (Minnesota) | 955.01 mi (1,536.94 km) |
| Norristown to Owensboro (Kentucky) | 653.13 mi (1,051.11 km) |
| Norristown to Owings Mills (Maryland) | 91.41 mi (147.11 km) |
| Norristown to Owosso (Michigan) | 497.77 mi (801.08 km) |
