Moreton Island is the 3rd largest sand island in the world and my favourite. I've been visiting/holidaying on the island for over 25 years and have seen many changes during this time, but I still keep going back.
A few years ago the lighthouse at Cape Moreton was handed over to National Parks, making it accessible to the public for the first time. It now also has some great information about the island's history in one of the keeper's cottages. The 23 m tall lighthouse was actually the first one built in Queensland in 1857. It was built by tradesmen and convicts!
The area surrounding the lighthouse is a fantastic viewpoint for whales (when in season) - binoculars are helpful though. You can also see dolphins, rays, dugongs and turtles in the waters surrounding the rocky outcrop on which the lighthouse sits.