| Porsgrunn to Oakley (California) | 5,174.16 mi (8,327.01 km) |
| Porsgrunn to Oakton (Virginia) | 3,867.19 mi (6,223.64 km) |
| Porsgrunn to Oakville (Missouri) | 4,309.98 mi (6,936.24 km) |
| Porsgrunn to Oatfield (Oregon) | 4,723.69 mi (7,602.04 km) |
| Porsgrunn to Ocala (Florida) | 4,572.70 mi (7,359.05 km) |
| Porsgrunn to Ocean Acres (New Jersey) | 3,720.14 mi (5,986.98 km) |
| Porsgrunn to Ocean City (New Jersey) | 3,756.41 mi (6,045.36 km) |
| Porsgrunn to Ocean Pines (Maryland) | 3,822.43 mi (6,151.61 km) |
| Porsgrunn to Ocean Pointe (Hawaii) | 6,835.86 mi (11,001.26 km) |
| Porsgrunn to Ocean Springs (Mississippi) | 4,722.33 mi (7,599.86 km) |
| Porsgrunn to Oceanside (California) | 5,373.92 mi (8,648.49 km) |
| Porsgrunn to Oceanside (New York) | 3,651.07 mi (5,875.83 km) |
| Porsgrunn to Ocoee (Florida) | 4,585.99 mi (7,380.43 km) |
| Porsgrunn to Oconomowoc (Wisconsin) | 3,993.50 mi (6,426.92 km) |
| Porsgrunn to Odenton (Maryland) | 3,837.33 mi (6,175.59 km) |
