| Philadelphia to Odenton (Maryland) | 105.55 mi (169.87 km) |
| Philadelphia to Odessa (Texas) | 1,614.60 mi (2,598.45 km) |
| Philadelphia to Ogden (Utah) | 1,919.16 mi (3,088.59 km) |
| Philadelphia to Oildale (California) | 2,395.60 mi (3,855.35 km) |
| Philadelphia to Ojus (Florida) | 1,013.14 mi (1,630.50 km) |
| Philadelphia to Okemos (Michigan) | 515.75 mi (830.02 km) |
| Philadelphia to Oklahoma City (Oklahoma) | 1,258.72 mi (2,025.71 km) |
| Philadelphia to Okmulgee (Oklahoma) | 1,176.08 mi (1,892.71 km) |
| Philadelphia to Olathe (Kansas) | 1,051.09 mi (1,691.57 km) |
| Philadelphia to Old Jamestown (Missouri) | 811.67 mi (1,306.25 km) |
| Philadelphia to Oldsmar (Florida) | 931.16 mi (1,498.55 km) |
| Philadelphia to Olean (New York) | 223.75 mi (360.09 km) |
| Philadelphia to Olive Branch (Mississippi) | 877.39 mi (1,412.02 km) |
| Philadelphia to Olivehurst (California) | 2,445.76 mi (3,936.07 km) |
| Philadelphia to Olney (Maryland) | 119.11 mi (191.69 km) |
