| Rockville to Romeoville (Illinois) | 602.03 mi (968.88 km) |
| Rockville to Romulus (Michigan) | 391.07 mi (629.36 km) |
| Rockville to Ronkonkoma (New York) | 244.33 mi (393.22 km) |
| Rockville to Roosevelt (New York) | 219.12 mi (352.64 km) |
| Rockville to Rosamond (California) | 2,265.80 mi (3,646.45 km) |
| Rockville to Rosaryville (Maryland) | 28.10 mi (45.22 km) |
| Rockville to Roscoe (Illinois) | 661.26 mi (1,064.19 km) |
| Rockville to Rose Hill (Virginia) | 20.62 mi (33.18 km) |
| Rockville to Roseburg (Oregon) | 2,389.62 mi (3,845.72 km) |
| Rockville to Rosedale (California) | 2,306.58 mi (3,712.08 km) |
| Rockville to Rosedale (Maryland) | 38.50 mi (61.95 km) |
| Rockville to Roselle (Illinois) | 607.39 mi (977.51 km) |
| Rockville to Roselle (New Jersey) | 187.95 mi (302.48 km) |
| Rockville to Roselle Park (New Jersey) | 188.16 mi (302.81 km) |
| Rockville to Rosemead (California) | 2,277.77 mi (3,665.72 km) |
