| Rockville to Ridgefield Park (New Jersey) | 206.21 mi (331.87 km) |
| Rockville to Ridgeland (Mississippi) | 860.34 mi (1,384.58 km) |
| Rockville to Ridgewood (New Jersey) | 207.63 mi (334.14 km) |
| Rockville to Rifle (Colorado) | 1,629.16 mi (2,621.87 km) |
| Rockville to Rincon (Georgia) | 521.79 mi (839.75 km) |
| Rockville to Ringwood (New Jersey) | 206.66 mi (332.58 km) |
| Rockville to Río Grande (Puerto Rico) | 1,583.16 mi (2,547.85 km) |
| Rockville to Rio Grande City (Texas) | 1,528.36 mi (2,459.66 km) |
| Rockville to Rio Linda (California) | 2,357.81 mi (3,794.53 km) |
| Rockville to Rio Rancho (New Mexico) | 1,639.82 mi (2,639.03 km) |
| Rockville to Rio Rico (Arizona) | 1,966.28 mi (3,164.43 km) |
| Rockville to Ripon (California) | 2,359.12 mi (3,796.63 km) |
| Rockville to River Edge (New Jersey) | 208.38 mi (335.35 km) |
| Rockville to River Falls (Wisconsin) | 887.27 mi (1,427.93 km) |
| Rockville to River Forest (Illinois) | 592.60 mi (953.69 km) |
