| Difficult Run to San Luis Obispo (California) | 2,378.66 mi (3,828.09 km) |
| Difficult Run to San Marcos (California) | 2,242.98 mi (3,609.73 km) |
| Difficult Run to San Marcos (Texas) | 1,324.98 mi (2,132.34 km) |
| Difficult Run to San Marino (California) | 2,268.81 mi (3,651.30 km) |
| Difficult Run to San Mateo (California) | 2,417.38 mi (3,890.39 km) |
| Difficult Run to San Pablo (California) | 2,411.08 mi (3,880.25 km) |
| Difficult Run to San Rafael (California) | 2,419.96 mi (3,894.55 km) |
| Difficult Run to San Ramon (California) | 2,393.59 mi (3,852.11 km) |
| Difficult Run to San Tan Valley (Arizona) | 1,940.21 mi (3,122.46 km) |
| Difficult Run to Sand Springs (Oklahoma) | 1,044.88 mi (1,681.57 km) |
| Difficult Run to Sandusky (Ohio) | 332.86 mi (535.68 km) |
| Difficult Run to Sandy (Oregon) | 2,313.46 mi (3,723.15 km) |
| Difficult Run to Sandy (Utah) | 1,825.16 mi (2,937.31 km) |
| Difficult Run to Sandy Springs (Georgia) | 519.46 mi (835.99 km) |
| Difficult Run to Sanford (Florida) | 733.96 mi (1,181.20 km) |
