| Difficult Run to Keizer (Oregon) | 2,352.68 mi (3,786.27 km) |
| Difficult Run to Keller (Texas) | 1,183.26 mi (1,904.28 km) |
| Difficult Run to Kelso (Washington) | 2,339.19 mi (3,764.56 km) |
| Difficult Run to Kemp Mill (Maryland) | 19.97 mi (32.14 km) |
| Difficult Run to Ken Caryl (Colorado) | 1,480.74 mi (2,383.02 km) |
| Difficult Run to Kendale Lakes (Florida) | 928.77 mi (1,494.71 km) |
| Difficult Run to Kendall (Florida) | 930.81 mi (1,497.99 km) |
| Difficult Run to Kendall Park (New Jersey) | 181.21 mi (291.63 km) |
| Difficult Run to Kendall West (Florida) | 929.23 mi (1,495.45 km) |
| Difficult Run to Kenmore (New York) | 291.77 mi (469.55 km) |
| Difficult Run to Kenmore (Washington) | 2,303.20 mi (3,706.64 km) |
| Difficult Run to Kenner (Louisiana) | 956.44 mi (1,539.24 km) |
| Difficult Run to Kennesaw (Georgia) | 525.70 mi (846.04 km) |
| Difficult Run to Kennett (Missouri) | 718.76 mi (1,156.74 km) |
| Difficult Run to Kennewick (Washington) | 2,161.27 mi (3,478.23 km) |
