Maria Island sits off Tasmania's east coast in the Tasman Sea, reached only by ferry, and combines more than a dozen preserved convict-era buildings with dense Eucalyptus forest.
It's listed among the Australian Convict Sites World Heritage listing for its 1800s penal history, and today the island is car-free and largely left to wildlife: Forester kangaroos, wombats and wallabies are common on the grassland, and birdwatchers come for over 125 species including the rare Forty-spotted Pardalote. Ferries run roughly 9am to 4:15pm, so it's a full-day trip rather than a quick stop.