| Difficult Run to Blue Island (Illinois) | 576.60 mi (927.94 km) |
| Difficult Run to Blue Springs (Missouri) | 908.07 mi (1,461.39 km) |
| Difficult Run to Bluffdale (Utah) | 1,830.62 mi (2,946.10 km) |
| Difficult Run to Bluffton (Indiana) | 434.15 mi (698.70 km) |
| Difficult Run to Bluffton (South Carolina) | 504.00 mi (811.11 km) |
| Difficult Run to Blythe (California) | 2,093.45 mi (3,369.08 km) |
| Difficult Run to Blytheville (Arkansas) | 718.34 mi (1,156.05 km) |
| Difficult Run to Boca Raton (Florida) | 880.14 mi (1,416.45 km) |
| Difficult Run to Boerne (Texas) | 1,368.08 mi (2,201.72 km) |
| Difficult Run to Bogalusa (Louisiana) | 903.23 mi (1,453.61 km) |
| Difficult Run to Boiling Springs (South Carolina) | 369.14 mi (594.08 km) |
| Difficult Run to Boise (Idaho) | 2,026.89 mi (3,261.97 km) |
| Difficult Run to Bolingbrook (Illinois) | 598.13 mi (962.59 km) |
| Difficult Run to Bolivar (Missouri) | 875.37 mi (1,408.78 km) |
| Difficult Run to Bon Air (Virginia) | 96.32 mi (155.01 km) |
