| Difficult Run to Rosemont (California) | 2,348.74 mi (3,779.93 km) |
| Difficult Run to Rosemount (Minnesota) | 902.42 mi (1,452.30 km) |
| Difficult Run to Rosenberg (Texas) | 1,234.07 mi (1,986.04 km) |
| Difficult Run to Roseville (California) | 2,343.00 mi (3,770.70 km) |
| Difficult Run to Roseville (Michigan) | 384.28 mi (618.44 km) |
| Difficult Run to Roseville (Minnesota) | 913.27 mi (1,469.77 km) |
| Difficult Run to Rossmoor (California) | 2,275.19 mi (3,661.56 km) |
| Difficult Run to Rossville (Maryland) | 56.28 mi (90.57 km) |
| Difficult Run to Roswell (Georgia) | 513.83 mi (826.93 km) |
| Difficult Run to Roswell (New Mexico) | 1,557.78 mi (2,507.01 km) |
| Difficult Run to Round Lake (Illinois) | 611.72 mi (984.46 km) |
| Difficult Run to Round Lake Beach (Illinois) | 611.34 mi (983.86 km) |
| Difficult Run to Round Rock (Texas) | 1,286.84 mi (2,070.97 km) |
| Difficult Run to Rowland Heights (California) | 2,260.56 mi (3,638.03 km) |
| Difficult Run to Rowlett (Texas) | 1,148.62 mi (1,848.53 km) |
