Portland Island was a custom map created for Battlefield 2 that was developed over a period of 12 months. The finished product was one of the most beautiful, detailed and largest city maps ever created for the game, including over 3,000 objects, and 300 buildings.
As the name suggests, the map was a replica of the "Portland" island which featured in the popular GTA Liberty City. The painstaking reconstruction process meant that the Battlefield 2 port was an almost identical replica of its GTA counterpart.
Upon release, Portland Island was downloaded over 1,000 times within the first week. Since then it has been downloaded over 10,000 times; making it one of the most popular user-created maps for Battlefield 2.