| Mason City to Oak Harbor (Washington) | 1,453.86 mi (2,339.76 km) |
| Mason City to Oak Hills (Oregon) | 1,465.51 mi (2,358.51 km) |
| Mason City to Oak Lawn (Illinois) | 294.87 mi (474.54 km) |
| Mason City to Oak Park (California) | 1,504.06 mi (2,420.55 km) |
| Mason City to Oak Park (Illinois) | 288.90 mi (464.93 km) |
| Mason City to Oak Park (Michigan) | 509.66 mi (820.23 km) |
| Mason City to Oak Ridge (Florida) | 1,207.25 mi (1,942.87 km) |
| Mason City to Oak Ridge (New Jersey) | 967.94 mi (1,557.75 km) |
| Mason City to Oak Ridge (Tennessee) | 685.88 mi (1,103.82 km) |
| Mason City to Oakdale (California) | 1,492.94 mi (2,402.65 km) |
| Mason City to Oakdale (Minnesota) | 127.59 mi (205.34 km) |
| Mason City to Oakland (California) | 1,561.01 mi (2,512.20 km) |
| Mason City to Oakland (New Jersey) | 980.87 mi (1,578.56 km) |
| Mason City to Oakland Park (Florida) | 1,383.49 mi (2,226.51 km) |
| Mason City to Oakleaf Plantation (Florida) | 1,093.69 mi (1,760.13 km) |
