| Rockville to Ramsey (New Jersey) | 209.66 mi (337.42 km) |
| Rockville to Rancho Cordova (California) | 2,349.99 mi (3,781.95 km) |
| Rockville to Rancho Cucamonga (California) | 2,248.82 mi (3,619.13 km) |
| Rockville to Rancho Mirage (California) | 2,196.73 mi (3,535.30 km) |
| Rockville to Rancho Palos Verdes (California) | 2,300.61 mi (3,702.47 km) |
| Rockville to Rancho San Diego (California) | 2,248.95 mi (3,619.33 km) |
| Rockville to Rancho Santa Margarita (California) | 2,262.79 mi (3,641.61 km) |
| Rockville to Randallstown (Maryland) | 27.48 mi (44.23 km) |
| Rockville to Rantoul (Illinois) | 590.44 mi (950.23 km) |
| Rockville to Rapid City (South Dakota) | 1,384.18 mi (2,227.63 km) |
| Rockville to Ravenna (Ohio) | 259.25 mi (417.22 km) |
| Rockville to Raymondville (Texas) | 1,475.20 mi (2,374.10 km) |
| Rockville to Raymore (Missouri) | 928.64 mi (1,494.50 km) |
| Rockville to Raytown (Missouri) | 927.51 mi (1,492.68 km) |
| Rockville to Reading (Ohio) | 389.96 mi (627.58 km) |
