| Imperial Beach to Olympia Heights (Florida) | 2,257.61 mi (3,633.28 km) |
| Imperial Beach to Omaha (Nebraska) | 1,304.74 mi (2,099.77 km) |
| Imperial Beach to On Top of the World Designated Place (Florida) | 2,071.01 mi (3,332.97 km) |
| Imperial Beach to Onalaska (Wisconsin) | 1,599.33 mi (2,573.87 km) |
| Imperial Beach to Oneida (New York) | 2,349.37 mi (3,780.94 km) |
| Imperial Beach to Oneonta (New York) | 2,377.11 mi (3,825.58 km) |
| Imperial Beach to Ontario (California) | 105.41 mi (169.64 km) |
| Imperial Beach to Ontario (Oregon) | 791.61 mi (1,273.98 km) |
| Imperial Beach to Opa-locka (Florida) | 2,258.19 mi (3,634.21 km) |
| Imperial Beach to Opelika (Alabama) | 1,840.27 mi (2,961.63 km) |
| Imperial Beach to Opelousas (Louisiana) | 1,477.54 mi (2,377.86 km) |
| Imperial Beach to Orange (California) | 94.51 mi (152.09 km) |
| Imperial Beach to Orange (Texas) | 1,385.80 mi (2,230.22 km) |
| Imperial Beach to Orange City (Florida) | 2,132.28 mi (3,431.58 km) |
| Imperial Beach to Orangeburg (South Carolina) | 2,090.11 mi (3,363.70 km) |
