| Darby to Odessa (Texas) | 1,606.79 mi (2,585.88 km) |
| Darby to Ogden (Utah) | 1,914.17 mi (3,080.56 km) |
| Darby to Oildale (California) | 2,389.62 mi (3,845.72 km) |
| Darby to Ojus (Florida) | 1,005.37 mi (1,617.99 km) |
| Darby to Okemos (Michigan) | 512.13 mi (824.19 km) |
| Darby to Oklahoma City (Oklahoma) | 1,251.28 mi (2,013.75 km) |
| Darby to Okmulgee (Oklahoma) | 1,168.56 mi (1,880.61 km) |
| Darby to Olathe (Kansas) | 1,044.60 mi (1,681.12 km) |
| Darby to Old Jamestown (Missouri) | 804.87 mi (1,295.31 km) |
| Darby to Oldsmar (Florida) | 922.62 mi (1,484.81 km) |
| Darby to Olean (New York) | 222.76 mi (358.49 km) |
| Darby to Olive Branch (Mississippi) | 869.09 mi (1,398.67 km) |
| Darby to Olivehurst (California) | 2,440.67 mi (3,927.87 km) |
| Darby to Olney (Maryland) | 110.32 mi (177.55 km) |
| Darby to Olympia (Washington) | 2,399.72 mi (3,861.97 km) |
