| Fort Oglethorpe to Olympia Heights (Florida) | 700.00 mi (1,126.55 km) |
| Fort Oglethorpe to Omaha (Nebraska) | 731.60 mi (1,177.40 km) |
| Fort Oglethorpe to On Top of the World Designated Place (Florida) | 438.22 mi (705.24 km) |
| Fort Oglethorpe to Onalaska (Wisconsin) | 695.39 mi (1,119.13 km) |
| Fort Oglethorpe to Oneida (New York) | 761.53 mi (1,225.57 km) |
| Fort Oglethorpe to Oneonta (New York) | 754.96 mi (1,215.00 km) |
| Fort Oglethorpe to Ontario (California) | 1,835.95 mi (2,954.67 km) |
| Fort Oglethorpe to Ontario (Oregon) | 1,791.64 mi (2,883.36 km) |
| Fort Oglethorpe to Opa-locka (Florida) | 691.01 mi (1,112.07 km) |
| Fort Oglethorpe to Opelika (Alabama) | 157.06 mi (252.77 km) |
| Fort Oglethorpe to Opelousas (Louisiana) | 500.33 mi (805.20 km) |
| Fort Oglethorpe to Orange (California) | 1,851.28 mi (2,979.35 km) |
| Fort Oglethorpe to Orange (Texas) | 596.66 mi (960.23 km) |
| Fort Oglethorpe to Orange City (Florida) | 474.80 mi (764.12 km) |
| Fort Oglethorpe to Orangeburg (South Carolina) | 269.20 mi (433.23 km) |
