| Difficult Run to Roy (Utah) | 1,830.23 mi (2,945.46 km) |
| Difficult Run to Royal Kunia (Hawaii) | 4,817.76 mi (7,753.44 km) |
| Difficult Run to Royal Oak (Michigan) | 393.04 mi (632.53 km) |
| Difficult Run to Royal Palm Beach (Florida) | 859.05 mi (1,382.51 km) |
| Difficult Run to Royse City (Texas) | 1,134.75 mi (1,826.20 km) |
| Difficult Run to Ruskin (Florida) | 826.75 mi (1,330.52 km) |
| Difficult Run to Russellville (Alabama) | 649.77 mi (1,045.70 km) |
| Difficult Run to Russellville (Arkansas) | 904.33 mi (1,455.37 km) |
| Difficult Run to Ruston (Louisiana) | 962.20 mi (1,548.51 km) |
| Difficult Run to Rutherford (New Jersey) | 217.06 mi (349.33 km) |
| Difficult Run to Rutland (Vermont) | 396.47 mi (638.05 km) |
| Difficult Run to Sabana Grande (Puerto Rico) | 1,567.80 mi (2,523.13 km) |
| Difficult Run to Sachse (Texas) | 1,148.45 mi (1,848.24 km) |
| Difficult Run to Saco (Maine) | 479.99 mi (772.47 km) |
| Difficult Run to Sacramento (California) | 2,354.30 mi (3,788.88 km) |
