| Gaithersburg to Haines City (Florida) | 802.43 mi (1,291.39 km) |
| Gaithersburg to Halawa (Hawaii) | 4,816.81 mi (7,751.90 km) |
| Gaithersburg to Half Moon Bay (California) | 2,429.31 mi (3,909.60 km) |
| Gaithersburg to Halfway (Maryland) | 44.64 mi (71.84 km) |
| Gaithersburg to Hallandale Beach (Florida) | 924.24 mi (1,487.42 km) |
| Gaithersburg to Haltom City (Texas) | 1,200.22 mi (1,931.57 km) |
| Gaithersburg to Ham Lake (Minnesota) | 919.05 mi (1,479.07 km) |
| Gaithersburg to Hamilton (Ohio) | 393.60 mi (633.44 km) |
| Gaithersburg to Hamilton Square (New Jersey) | 155.59 mi (250.41 km) |
| Gaithersburg to Hammond (Indiana) | 567.10 mi (912.66 km) |
| Gaithersburg to Hammond (Louisiana) | 957.21 mi (1,540.48 km) |
| Gaithersburg to Hammonton (New Jersey) | 135.46 mi (218.00 km) |
| Gaithersburg to Hampton (Virginia) | 150.93 mi (242.90 km) |
| Gaithersburg to Hampton Bays (New York) | 275.63 mi (443.59 km) |
| Gaithersburg to Hamtramck (Michigan) | 379.65 mi (610.98 km) |
