Portsea Island

:"There is also a town in Australia named Portsea, Victoria after this island."

Infobox Islands
name = Portsea

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image caption = Closeup map of Portsea Island
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Location map|Hampshire|lat=50.79243|long=-1.09194
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location = Solent
coordinates = coord|50.79243|N|1.09194|W|display=inline
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country = England
country admin divisions title = County
country admin divisions = flag|Hampshire
country admin divisions title 1 = City
country admin divisions 1 = Portsmouth
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population = 147,088
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Portsea Island is a small, flat and low lying island just off the south coast of England. The island is totally within, and contains a large proportion of the city of Portsmouth. It has the largest population of any island in the British Isles, after the mainlands of Great Britain and Ireland.

To the east lies Langstone Harbour, and to the west is Portsmouth Harbour. To the south it faces into the Solent. A small channel, known as Ports Creek, separates the island from the mainland, Great Britain.

Three road bridges, a pedestrian and cyclist bridge and a rail bridge connect the island to the mainland. In addition there are ferry services to Gosport (on the mainland), Hayling Island and the Isle of Wight.

There are seven bridges. A small bridge joins it to Whale Island.

The name of Portsea is also used for the administrative district of Portsmouth, located in the south-west corner of the island.