| Mason City to Duluth (Minnesota) | 255.89 mi (411.82 km) |
| Mason City to Dumas (Texas) | 686.12 mi (1,104.21 km) |
| Mason City to Dumont (New Jersey) | 994.93 mi (1,601.18 km) |
| Mason City to Duncan (Oklahoma) | 646.47 mi (1,040.39 km) |
| Mason City to Duncanville (Texas) | 753.16 mi (1,212.09 km) |
| Mason City to Dundalk (Maryland) | 906.94 mi (1,459.58 km) |
| Mason City to Dunedin (Florida) | 1,194.88 mi (1,922.97 km) |
| Mason City to Dunkirk (New York) | 703.56 mi (1,132.27 km) |
| Mason City to Dunmore (Pennsylvania) | 905.53 mi (1,457.30 km) |
| Mason City to Dunwoody (Georgia) | 796.06 mi (1,281.13 km) |
| Mason City to Durango (Colorado) | 872.98 mi (1,404.93 km) |
| Mason City to Durant (Oklahoma) | 655.42 mi (1,054.79 km) |
| Mason City to Durham (North Carolina) | 906.54 mi (1,458.94 km) |
| Mason City to Dyer (Indiana) | 312.20 mi (502.44 km) |
| Mason City to Dyersburg (Tennessee) | 531.07 mi (854.68 km) |
