| Difficult Run to Kenosha (Wisconsin) | 606.61 mi (976.24 km) |
| Difficult Run to Kent (Ohio) | 263.04 mi (423.32 km) |
| Difficult Run to Kent (Washington) | 2,302.28 mi (3,705.16 km) |
| Difficult Run to Kentwood (Michigan) | 510.73 mi (821.94 km) |
| Difficult Run to Kerman (California) | 2,315.14 mi (3,725.85 km) |
| Difficult Run to Kernersville (North Carolina) | 244.52 mi (393.52 km) |
| Difficult Run to Kerrville (Texas) | 1,378.88 mi (2,219.10 km) |
| Difficult Run to Kettering (Maryland) | 30.03 mi (48.33 km) |
| Difficult Run to Kettering (Ohio) | 367.73 mi (591.80 km) |
| Difficult Run to Kewanee (Illinois) | 683.78 mi (1,100.43 km) |
| Difficult Run to Key Biscayne (Florida) | 927.36 mi (1,492.43 km) |
| Difficult Run to Key Largo (Florida) | 968.66 mi (1,558.91 km) |
| Difficult Run to Key West (Florida) | 1,023.88 mi (1,647.78 km) |
| Difficult Run to Keystone (Florida) | 802.93 mi (1,292.19 km) |
| Difficult Run to Kihei (Hawaii) | 4,759.38 mi (7,659.49 km) |
