| Galveston to Odessa (Texas) | 479.12 mi (771.07 km) |
| Galveston to Ogden (Utah) | 1,266.11 mi (2,037.60 km) |
| Galveston to Oildale (California) | 1,468.13 mi (2,362.73 km) |
| Galveston to Ojus (Florida) | 929.45 mi (1,495.81 km) |
| Galveston to Okemos (Michigan) | 1,096.97 mi (1,765.41 km) |
| Galveston to Oklahoma City (Oklahoma) | 456.09 mi (734.01 km) |
| Galveston to Okmulgee (Oklahoma) | 444.55 mi (715.44 km) |
| Galveston to Olathe (Kansas) | 665.72 mi (1,071.37 km) |
| Galveston to Old Jamestown (Missouri) | 712.95 mi (1,147.38 km) |
| Galveston to Oldsmar (Florida) | 745.30 mi (1,199.44 km) |
| Galveston to Olean (New York) | 1,276.23 mi (2,053.89 km) |
| Galveston to Olive Branch (Mississippi) | 492.73 mi (792.97 km) |
| Galveston to Olivehurst (California) | 1,660.83 mi (2,672.84 km) |
| Galveston to Olney (Maryland) | 1,223.08 mi (1,968.36 km) |
| Galveston to Olympia (Washington) | 1,938.00 mi (3,118.92 km) |
