| Gaithersburg to Odessa (Texas) | 1,493.86 mi (2,404.13 km) |
| Gaithersburg to Ogden (Utah) | 1,828.11 mi (2,942.06 km) |
| Gaithersburg to Oildale (California) | 2,292.83 mi (3,689.95 km) |
| Gaithersburg to Ojus (Florida) | 926.42 mi (1,490.92 km) |
| Gaithersburg to Okemos (Michigan) | 449.41 mi (723.25 km) |
| Gaithersburg to Oklahoma City (Oklahoma) | 1,141.53 mi (1,837.11 km) |
| Gaithersburg to Okmulgee (Oklahoma) | 1,058.11 mi (1,702.86 km) |
| Gaithersburg to Olathe (Kansas) | 943.97 mi (1,519.17 km) |
| Gaithersburg to Old Jamestown (Missouri) | 701.71 mi (1,129.29 km) |
| Gaithersburg to Oldsmar (Florida) | 827.28 mi (1,331.37 km) |
| Gaithersburg to Olean (New York) | 213.43 mi (343.49 km) |
| Gaithersburg to Olive Branch (Mississippi) | 753.16 mi (1,212.09 km) |
| Gaithersburg to Olivehurst (California) | 2,353.04 mi (3,786.85 km) |
| Gaithersburg to Olney (Maryland) | 7.63 mi (12.28 km) |
| Gaithersburg to Olympia (Washington) | 2,333.88 mi (3,756.02 km) |
