| Porsgrunn to Orangevale (California) | 5,119.85 mi (8,239.60 km) |
| Porsgrunn to Orchards (Washington) | 4,705.00 mi (7,571.97 km) |
| Porsgrunn to Orcutt (California) | 5,343.59 mi (8,599.68 km) |
| Porsgrunn to Oregon (Ohio) | 3,916.05 mi (6,302.27 km) |
| Porsgrunn to Oregon (Wisconsin) | 4,030.17 mi (6,485.94 km) |
| Porsgrunn to Oregon City (Oregon) | 4,728.12 mi (7,609.17 km) |
| Porsgrunn to Orem (Utah) | 4,798.51 mi (7,722.46 km) |
| Porsgrunn to Orinda (California) | 5,191.74 mi (8,355.29 km) |
| Porsgrunn to Orland Park (Illinois) | 4,056.82 mi (6,528.82 km) |
| Porsgrunn to Orlando (Florida) | 4,585.17 mi (7,379.12 km) |
| Porsgrunn to Ormond Beach (Florida) | 4,530.23 mi (7,290.70 km) |
| Porsgrunn to Oro Valley (Arizona) | 5,263.09 mi (8,470.12 km) |
| Porsgrunn to Oroville (California) | 5,075.91 mi (8,168.89 km) |
| Porsgrunn to Oshkosh (Wisconsin) | 3,944.63 mi (6,348.27 km) |
| Porsgrunn to Oskaloosa (Iowa) | 4,219.09 mi (6,789.98 km) |
