| Difficult Run to Romeoville (Illinois) | 596.96 mi (960.72 km) |
| Difficult Run to Romulus (Michigan) | 390.35 mi (628.20 km) |
| Difficult Run to Ronkonkoma (New York) | 259.64 mi (417.85 km) |
| Difficult Run to Roosevelt (New York) | 234.52 mi (377.42 km) |
| Difficult Run to Rosamond (California) | 2,256.82 mi (3,632.00 km) |
| Difficult Run to Rosaryville (Maryland) | 29.51 mi (47.50 km) |
| Difficult Run to Roscoe (Illinois) | 657.19 mi (1,057.64 km) |
| Difficult Run to Rose Hill (Virginia) | 15.08 mi (24.27 km) |
| Difficult Run to Roseburg (Oregon) | 2,384.83 mi (3,838.02 km) |
| Difficult Run to Rosedale (California) | 2,297.93 mi (3,698.16 km) |
| Difficult Run to Rosedale (Maryland) | 53.70 mi (86.42 km) |
| Difficult Run to Roselle (Illinois) | 602.93 mi (970.32 km) |
| Difficult Run to Roselle (New Jersey) | 203.72 mi (327.86 km) |
| Difficult Run to Roselle Park (New Jersey) | 203.94 mi (328.22 km) |
| Difficult Run to Rosemead (California) | 2,268.45 mi (3,650.72 km) |
