| Porsgrunn to Imola | 1,023.47 mi (1,647.12 km) |
| Porsgrunn to Impruneta | 1,068.26 mi (1,719.20 km) |
| Porsgrunn to Induno Olona | 917.29 mi (1,476.23 km) |
| Porsgrunn to Inverigo | 924.85 mi (1,488.41 km) |
| Porsgrunn to Inveruno | 940.27 mi (1,513.23 km) |
| Porsgrunn to Inzago | 938.49 mi (1,510.36 km) |
| Porsgrunn to Iseo | 929.90 mi (1,496.53 km) |
| Porsgrunn to Isernia | 1,225.69 mi (1,972.56 km) |
| Porsgrunn to Isola Capo Rizzuto | 1,430.25 mi (2,301.77 km) |
| Porsgrunn to Isola del Liri | 1,216.18 mi (1,957.25 km) |
| Porsgrunn to Isola della Scala | 958.23 mi (1,542.13 km) |
| Porsgrunn to Isola Vicentina | 934.34 mi (1,503.68 km) |
| Porsgrunn to Ispica | 1,560.48 mi (2,511.35 km) |
| Porsgrunn to Istrana | 933.38 mi (1,502.14 km) |
| Porsgrunn to Itri | 1,243.14 mi (2,000.64 km) |
