| Difficult Run to River Ridge (Louisiana) | 957.38 mi (1,540.76 km) |
| Difficult Run to Riverbank (California) | 2,342.09 mi (3,769.24 km) |
| Difficult Run to Riverdale (Georgia) | 539.08 mi (867.57 km) |
| Difficult Run to Riverdale (Illinois) | 574.13 mi (923.97 km) |
| Difficult Run to Riverside (California) | 2,234.76 mi (3,596.50 km) |
| Difficult Run to Riverside (Ohio) | 367.01 mi (590.64 km) |
| Difficult Run to Riverton (Utah) | 1,831.54 mi (2,947.57 km) |
| Difficult Run to Riverton (Wyoming) | 1,636.09 mi (2,633.03 km) |
| Difficult Run to Riverview (Florida) | 816.78 mi (1,314.47 km) |
| Difficult Run to Riverview (Michigan) | 381.09 mi (613.31 km) |
| Difficult Run to Riviera Beach (Florida) | 852.14 mi (1,371.38 km) |
| Difficult Run to Riviera Beach (Maryland) | 47.62 mi (76.64 km) |
| Difficult Run to Roanoke (Virginia) | 180.92 mi (291.16 km) |
| Difficult Run to Roanoke Rapids (North Carolina) | 170.52 mi (274.43 km) |
| Difficult Run to Robbinsdale (Minnesota) | 921.64 mi (1,483.24 km) |
