| Rockville to Hillcrest Heights (Maryland) | 19.87 mi (31.97 km) |
| Rockville to Hilliard (Ohio) | 326.37 mi (525.24 km) |
| Rockville to Hillsboro (Oregon) | 2,348.51 mi (3,779.56 km) |
| Rockville to Hillsborough (California) | 2,427.13 mi (3,906.08 km) |
| Rockville to Hillsborough (New Jersey) | 165.31 mi (266.03 km) |
| Rockville to Hilo (Hawaii) | 4,738.37 mi (7,625.66 km) |
| Rockville to Hilton Head Island (South Carolina) | 517.20 mi (832.35 km) |
| Rockville to Hinesville (Georgia) | 560.59 mi (902.19 km) |
| Rockville to Hinsdale (Illinois) | 596.25 mi (959.57 km) |
| Rockville to Hobart (Indiana) | 558.59 mi (898.96 km) |
| Rockville to Hobbs (New Mexico) | 1,514.13 mi (2,436.75 km) |
| Rockville to Hobe Sound (Florida) | 847.53 mi (1,363.96 km) |
| Rockville to Hoboken (New Jersey) | 201.59 mi (324.43 km) |
| Rockville to Hockessin (Delaware) | 92.34 mi (148.61 km) |
| Rockville to Hoffman Estates (Illinois) | 611.96 mi (984.85 km) |
