| Difficult Run to Lindsay (California) | 2,274.11 mi (3,659.83 km) |
| Difficult Run to Linganore (Maryland) | 35.40 mi (56.97 km) |
| Difficult Run to Lino Lakes (Minnesota) | 914.05 mi (1,471.03 km) |
| Difficult Run to Linthicum (Maryland) | 42.42 mi (68.27 km) |
| Difficult Run to Linton Hall (Virginia) | 15.90 mi (25.59 km) |
| Difficult Run to Lisle (Illinois) | 599.35 mi (964.57 km) |
| Difficult Run to Lithia Springs (Georgia) | 538.46 mi (866.56 km) |
| Difficult Run to Little Canada (Minnesota) | 910.42 mi (1,465.17 km) |
| Difficult Run to Little Chute (Wisconsin) | 677.44 mi (1,090.23 km) |
| Difficult Run to Little Elm (Texas) | 1,160.25 mi (1,867.24 km) |
| Difficult Run to Little Ferry (New Jersey) | 220.95 mi (355.58 km) |
| Difficult Run to Little Rock (Arkansas) | 877.75 mi (1,412.60 km) |
| Difficult Run to Littleton (Colorado) | 1,475.57 mi (2,374.69 km) |
| Difficult Run to Live Oak (California) | 2,411.21 mi (3,880.46 km) |
| Difficult Run to Live Oak (Texas) | 1,357.42 mi (2,184.55 km) |
