6:24 p.m.: You’re on the verge of sensory overload. It’s golden hour at the new 160-room One&Only Hayman Island, a green haven on the Great Barrier Reef, and you’re reliving the day’s adventures. It began with a seaplane flight over this, the world’s largest living structure, touching down to snorkel in a pristine lagoon that exploded with color: rainbow-hued parrot fish bobbing among forests of staghorn coral, glowing purple and pink; green turtles and manta rays commuting casually by. (And don’t forget the giant clams, whose magenta lips slowly closed into contented grins as you swam past.) Lunch was a picnic and a chilled Barossa Valley rosé on the blazing-white sands of Coconut Beach. Now you’re back in a breezy cabana, met by a server with a tray of tart passion-fruit daiquiris to cleanse your palate for the evening ahead. What next? Take a short hike to Sunset Peak to catch the day’s last light? Maybe. Book an “Ocean Dreaming” massage, performed as you float on the warm tides of the Coral Sea? That sounds more like it. Then you remember you’ve planned a kayak trip tomorrow morning to one of Hayman’s secluded coves, and decide it’s best to tuck in early. So you head back to your suite, order up a platter of Sydney rock oysters, and count the shooting stars.