| Difficult Run to Burley (Idaho) | 1,910.09 mi (3,074.00 km) |
| Difficult Run to Burlingame (California) | 2,419.59 mi (3,893.95 km) |
| Difficult Run to Burlington (Iowa) | 741.73 mi (1,193.70 km) |
| Difficult Run to Burlington (Kentucky) | 396.18 mi (637.58 km) |
| Difficult Run to Burlington (North Carolina) | 227.23 mi (365.69 km) |
| Difficult Run to Burlington (Vermont) | 440.36 mi (708.69 km) |
| Difficult Run to Burlington (Wisconsin) | 627.52 mi (1,009.89 km) |
| Difficult Run to Burnsville (Minnesota) | 912.64 mi (1,468.75 km) |
| Difficult Run to Burr Ridge (Illinois) | 590.17 mi (949.78 km) |
| Difficult Run to Burton (Michigan) | 432.39 mi (695.87 km) |
| Difficult Run to Burtonsville (Maryland) | 26.62 mi (42.85 km) |
| Difficult Run to Butler (Pennsylvania) | 191.31 mi (307.88 km) |
| Difficult Run to Butte (Montana) | 1,848.78 mi (2,975.32 km) |
| Difficult Run to Byram (Mississippi) | 861.35 mi (1,386.22 km) |
| Difficult Run to Cabot (Arkansas) | 853.70 mi (1,373.90 km) |
