| Porsgrunn to Odessa (Texas) | 5,055.34 mi (8,135.78 km) |
| Porsgrunn to Ogden (Utah) | 4,748.34 mi (7,641.71 km) |
| Porsgrunn to Oildale (California) | 5,276.23 mi (8,491.28 km) |
| Porsgrunn to Ojus (Florida) | 4,689.55 mi (7,547.10 km) |
| Porsgrunn to Okemos (Michigan) | 3,889.50 mi (6,259.55 km) |
| Porsgrunn to Oklahoma City (Oklahoma) | 4,700.17 mi (7,564.20 km) |
| Porsgrunn to Okmulgee (Oklahoma) | 4,646.55 mi (7,477.91 km) |
| Porsgrunn to Olathe (Kansas) | 4,421.50 mi (7,115.71 km) |
| Porsgrunn to Old Jamestown (Missouri) | 4,286.69 mi (6,898.77 km) |
| Porsgrunn to Oldsmar (Florida) | 4,654.89 mi (7,491.32 km) |
| Porsgrunn to Olean (New York) | 3,732.37 mi (6,006.67 km) |
| Porsgrunn to Olive Branch (Mississippi) | 4,494.10 mi (7,232.55 km) |
| Porsgrunn to Olivehurst (California) | 5,102.36 mi (8,211.46 km) |
| Porsgrunn to Olney (Maryland) | 3,845.56 mi (6,188.83 km) |
| Porsgrunn to Olympia (Washington) | 4,626.90 mi (7,446.27 km) |
