| Gaithersburg to Buena Park (California) | 2,275.53 mi (3,662.12 km) |
| Gaithersburg to Buenaventura Lakes (Florida) | 782.95 mi (1,260.03 km) |
| Gaithersburg to Buffalo (Minnesota) | 947.19 mi (1,524.36 km) |
| Gaithersburg to Buffalo (New York) | 273.88 mi (440.77 km) |
| Gaithersburg to Buffalo Grove (Illinois) | 600.62 mi (966.60 km) |
| Gaithersburg to Buford (Georgia) | 510.89 mi (822.20 km) |
| Gaithersburg to Bull Run (Virginia) | 29.53 mi (47.53 km) |
| Gaithersburg to Bullhead City (Arizona) | 2,060.59 mi (3,316.20 km) |
| Gaithersburg to Burbank (California) | 2,284.38 mi (3,676.36 km) |
| Gaithersburg to Burbank (Illinois) | 583.17 mi (938.52 km) |
| Gaithersburg to Burien (Washington) | 2,306.28 mi (3,711.60 km) |
| Gaithersburg to Burkburnett (Texas) | 1,231.61 mi (1,982.08 km) |
| Gaithersburg to Burke (Virginia) | 24.83 mi (39.97 km) |
| Gaithersburg to Burke Centre (Virginia) | 24.24 mi (39.01 km) |
| Gaithersburg to Burleson (Texas) | 1,213.07 mi (1,952.25 km) |
