| Difficult Run to Marysville (California) | 2,350.29 mi (3,782.42 km) |
| Difficult Run to Marysville (Ohio) | 333.02 mi (535.95 km) |
| Difficult Run to Marysville (Washington) | 2,298.43 mi (3,698.96 km) |
| Difficult Run to Maryville (Missouri) | 936.33 mi (1,506.88 km) |
| Difficult Run to Maryville (Tennessee) | 424.43 mi (683.05 km) |
| Difficult Run to Mason (Ohio) | 374.01 mi (601.91 km) |
| Difficult Run to Mason City (Iowa) | 875.22 mi (1,408.54 km) |
| Difficult Run to Massapequa (New York) | 239.24 mi (385.02 km) |
| Difficult Run to Massapequa Park (New York) | 240.68 mi (387.33 km) |
| Difficult Run to Massillon (Ohio) | 256.95 mi (413.52 km) |
| Difficult Run to Mastic (New York) | 272.58 mi (438.67 km) |
| Difficult Run to Mastic Beach (New York) | 271.73 mi (437.31 km) |
| Difficult Run to Matteson (Illinois) | 577.16 mi (928.86 km) |
| Difficult Run to Matthews (North Carolina) | 320.43 mi (515.69 km) |
| Difficult Run to Mattoon (Illinois) | 590.85 mi (950.88 km) |
