How many places in Australia are called Post Office Island?

There is one place named Post Office Island in Australia.

All places in the world called "Post Office Island".

Location Post Office Island:

• Western Australia

Cities

Kingston (5)
Gladstone (5)
Hamilton (5)
Springfield (4)
Woodstock (4)
Darlington (4)
Rosedale (4)
Richmond (4)
Gordon (4)
Windsor (4)
Newstead (4)
Cremorne (4)
Salisbury (3)
Stony Creek (3)
Dundas (3)
Kangaroo Flat (3)
Swan Reach (3)
Beaconsfield (3)
Bridgewater (3)
Elliott (3)
Forest Hill (3)
Red Hill (3)
Warburton (3)
Williamstown (3)
Middleton (3)
Sassafras (3)
Somerton (3)
Wattle Flat (3)
Black Springs (3)
Flinders (3)