| Didcot to Odessa (Texas) | 4,960.75 mi (7,983.56 km) |
| Didcot to Ogden (Utah) | 4,797.68 mi (7,721.12 km) |
| Didcot to Oildale (California) | 5,346.77 mi (8,604.79 km) |
| Didcot to Ojus (Florida) | 4,368.99 mi (7,031.21 km) |
| Didcot to Okemos (Michigan) | 3,740.62 mi (6,019.94 km) |
| Didcot to Oklahoma City (Oklahoma) | 4,591.44 mi (7,389.22 km) |
| Didcot to Okmulgee (Oklahoma) | 4,526.70 mi (7,285.01 km) |
| Didcot to Olathe (Kansas) | 4,318.04 mi (6,949.21 km) |
| Didcot to Old Jamestown (Missouri) | 4,147.43 mi (6,674.64 km) |
| Didcot to Oldsmar (Florida) | 4,369.47 mi (7,031.98 km) |
| Didcot to Olean (New York) | 3,533.22 mi (5,686.17 km) |
| Didcot to Olive Branch (Mississippi) | 4,319.48 mi (6,951.53 km) |
| Didcot to Olivehurst (California) | 5,215.13 mi (8,392.94 km) |
| Didcot to Olney (Maryland) | 3,607.72 mi (5,806.07 km) |
| Didcot to Olympia (Washington) | 4,796.61 mi (7,719.40 km) |
