| Gaithersburg to Homer Glen (Illinois) | 589.92 mi (949.38 km) |
| Gaithersburg to Homestead (Florida) | 962.88 mi (1,549.61 km) |
| Gaithersburg to Homewood (Alabama) | 662.05 mi (1,065.46 km) |
| Gaithersburg to Homewood (Illinois) | 574.68 mi (924.86 km) |
| Gaithersburg to Homosassa Springs (Florida) | 775.38 mi (1,247.85 km) |
| Gaithersburg to Honeygo (Maryland) | 45.97 mi (73.98 km) |
| Gaithersburg to Honolulu (Hawaii) | 4,814.83 mi (7,748.73 km) |
| Gaithersburg to Hoover (Alabama) | 665.69 mi (1,071.33 km) |
| Gaithersburg to Hopatcong (New Jersey) | 184.51 mi (296.95 km) |
| Gaithersburg to Hope Mills (North Carolina) | 303.35 mi (488.20 km) |
| Gaithersburg to Hopewell (Virginia) | 127.43 mi (205.08 km) |
| Gaithersburg to Hopkins (Minnesota) | 920.13 mi (1,480.80 km) |
| Gaithersburg to Hopkinsville (Kentucky) | 580.67 mi (934.50 km) |
| Gaithersburg to Horizon City (Texas) | 1,702.76 mi (2,740.34 km) |
| Gaithersburg to Horizon West (Florida) | 780.56 mi (1,256.19 km) |
