IT IS in the Melway - but you would never try to drive there. It is home to thousands of part-time residents who travel from around the world to spend summer there - but few Melburnians have ever visited.
It is in fact internationally recognised as a special place, but a lot of Victorians have never heard of it. Ladies and gentlemen, introducing Mud Islands, a group of three special islands in the southern part of Port Phillip Bay, just a few kilometres east of Queenscliff and north-east of Portsea.
No people live on the islands, which are part of the Port Phillip Heads Marine National Park and considered a wetland of ''international importance''. But just as the populations of nearby coastal destinations such as Queenscliff, Portsea, Sorrento and Rye swell by thousands at this time of year, so too does the population of Mud Islands.
The international visitors, all migratory birds, come from as far afield as Alaska and Siberia to nest, rest and feed there, in an isolated location that affords birds a level of protection not commonly found.
The protection is due to many factors. The islands are located in an area known as the Great Sands, so the surrounding water is very shallow, especially at low tide. Access via boats is very difficult, and many would-be visitors have been left stranded on the sand banks.
Parks Victoria marine ranger Stephen Tuohy says that the lack of human disturbance makes Mud Islands, which cover 86 hectares including a central lagoon, a desirable place for birds. The lack of people reduces the risk of the nests of ground-nesting birds being trampled, as can happen elsewhere.
''Mud Islands is a very, very important sanctuary for birds, particularly because of the fact that access there is so limited for many people. So, it provides a nesting haven for numerous species of shore birds and wader birds,'' Mr Tuohy says.
''There's such a diversity of species there. It's a very significant habitat.''
The islands are also protected by the marine national park status, which means nothing can be taken from them, and by being a Ramsar-listed wetland.
The birds of Mud Islands are not threatened by reptiles, foxes, cats, dogs or other animals that might attack them, because none of these animals lives on the islands. The islands are also free of rabbits, so birds do not have to compete with them for habitat.
But, it must be said, the islands are not predator free. When Fairfax Media visits Mud Islands with Mr Tuohy a handful of predators circle above. The birds of prey, three swamp harriers, cruise high above, looking for a meal.
Also keeping an eye on the islands today is a small group of birdwatchers and sightseers, who have been brought here by tour company South Bay Eco Adventures.
Guide Tania Ireton, president of BirdLife Bayside, says the islands are ''an incredibly important area for migratory shore birds that fly all the way from Alaska and Siberia to Australia every year''.
''They come down here and feed up during our summer and then fly all the way back to breed. It's also a very important area for a lot of Australia's birds - ibis, spoonbill, pelicans, cormorants - that breed here.''
Ms Ireton says the lagoon at Mud Islands is a highlight. ''It is absolutely magical. It's just an area that's totally protected. At high tide you've got migratory waders, you've got pelicans, egrets, herons - all in there feeding. And it's so close to Melbourne,'' she says.
''It's one of the best birdwatching places in Melbourne, especially for migratory shore birds. And a lot of people don't know about it. It's one of our best kept secrets.''