| Herndon to Odessa (Texas) | 1,482.43 mi (2,385.74 km) |
| Herndon to Ogden (Utah) | 1,822.28 mi (2,932.67 km) |
| Herndon to Oildale (California) | 2,284.98 mi (3,677.32 km) |
| Herndon to Ojus (Florida) | 913.44 mi (1,470.04 km) |
| Herndon to Okemos (Michigan) | 448.69 mi (722.09 km) |
| Herndon to Oklahoma City (Oklahoma) | 1,131.03 mi (1,820.21 km) |
| Herndon to Okmulgee (Oklahoma) | 1,047.44 mi (1,685.69 km) |
| Herndon to Olathe (Kansas) | 935.65 mi (1,505.78 km) |
| Herndon to Old Jamestown (Missouri) | 692.98 mi (1,115.24 km) |
| Herndon to Oldsmar (Florida) | 813.12 mi (1,308.58 km) |
| Herndon to Olean (New York) | 221.91 mi (357.13 km) |
| Herndon to Olive Branch (Mississippi) | 740.74 mi (1,192.10 km) |
| Herndon to Olivehurst (California) | 2,346.85 mi (3,776.89 km) |
| Herndon to Olney (Maryland) | 20.85 mi (33.56 km) |
| Herndon to Olympia (Washington) | 2,331.21 mi (3,751.71 km) |
