| Difficult Run to Arroyo Grande (California) | 2,377.42 mi (3,826.08 km) |
| Difficult Run to Artesia (California) | 2,273.26 mi (3,658.45 km) |
| Difficult Run to Artesia (New Mexico) | 1,566.19 mi (2,520.54 km) |
| Difficult Run to Artondale (Washington) | 2,322.52 mi (3,737.74 km) |
| Difficult Run to Arvada (Colorado) | 1,480.58 mi (2,382.77 km) |
| Difficult Run to Arvin (California) | 2,282.24 mi (3,672.91 km) |
| Difficult Run to Asbury Lake (Florida) | 661.71 mi (1,064.92 km) |
| Difficult Run to Asbury Park (New Jersey) | 199.71 mi (321.40 km) |
| Difficult Run to Ashburn (Virginia) | 10.98 mi (17.67 km) |
| Difficult Run to Asheboro (North Carolina) | 258.45 mi (415.94 km) |
| Difficult Run to Asheville (North Carolina) | 367.30 mi (591.12 km) |
| Difficult Run to Ashland (California) | 2,404.31 mi (3,869.37 km) |
| Difficult Run to Ashland (Kentucky) | 287.33 mi (462.42 km) |
| Difficult Run to Ashland (Ohio) | 296.29 mi (476.83 km) |
| Difficult Run to Ashland (Oregon) | 2,363.86 mi (3,804.26 km) |
