If you are in a wheelchair visiting Sydney, getting into town is a breeze by using the subway from the airport to the centre of town.
Once downtown, buy a day or weekly pass. The rails are wheelchair friendly as are the Sydney Ferries. Using the ferries is a great way to explore the harbour and the city by getting off a various points. Some docks, like Neutral Bay, lead to steep hills up, so you may need to ask for a push, but if you smile, the Aussies will always help!
My recommendation is a visit to Manly.
North America's Disabled Adventurer.
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