Rottnest Island is very rich in history and is located on Australia's West Coast a little south of Perth. It used to be used as a military base during the war and an unique Australian animal called the Quokka is found there. While at the island you could look for this animal, see the amazing Reef, relax at the multiple beaches, or swim in the perfect water. You could explore the island by bike which is surely the best way and while there you could buy a bike and snorkel package. You could also do ferry transfers and Perth City transfers to the Rottnest Island. This island is great and there is a lot to do here.
You can take a small ferry ride Cairns to Fitzroy Island. Fitzroy Island is off the beaten track and not as crowded as nearby Green Island. While there you could go on the trampoline in the ocean, go to the nudist beach, go to the beach front bar. You could also kayak, snorkel, paddle board, and go on an enchanted rain forest walk. You could also go to the Great Barrier Reef which is very close too. That is what you could do while at Fitzroy Island.
Lord Howe Island
Lord Howe Island is 600 kilometers south east of Sydney and to get there you need to travel by plane. While there you can explore the volcanic remnant that boasts tall mountain peaks, coral pools, go on walking trails and see a lot of wildlife. It may be a little expensive to come here but there is a plethora of things to do and it is a wonderful spot. That is what you could do while at Lord Howe Island.
Kangaroo Island is a very unique and different island. Here you get to see Kangaroos, seal colonies, Koalas, and Wombats. Those are some of the exotic animals that live there. There are also Sand Dunes of Little Sahara, cliff formations that are rocky, caves, and the Flinders Chase National Park. Those are some physical traits to the land that are also amazing. You can go on a 2 or 3 day tour from Adelaide, Australia which is a great amount of time exploring the Kangaroo Island.
Great Keppel Island
If you want to explore beyond the backpacking trail than Great Keppel Island is the perfect spot. There are 17 white sandy beaches there and clear water that make it perfect for you to explore the Great Barrier Reef. To get there you could either take the Greyhound Bus, Ferry Transfers, or accommodation at Emu Beach Backpackers. There is a lot to do here and it is a great island.
Bruny Island is south of Hobart, Tasmania and it is far from the tourist trail. It is a great spot to visit and is as far south you could go on land before touching Antarctica. While there you could see the fairy penguins and seal colonies, go on a few rainforest walks, amazing beach walks, and look at towering cliffs.