Kakadu is the largest national park in Australia, up in the Northern Territory, and people have lived in it without a break for something like 65,000 years. The record is on the rock. At Ubirr a loop runs shelter to shelter beneath the crimson sandstone of the Arnhem Land escarpment, past paintings of barramundi, mullet, goanna, echidna and yams. Each animal is drawn with its bones and organs showing, which is what x-ray art means. Together they are a catalogue of what people ate here over the last fifteen hundred years. Only the last scramble gains height, and from the top you get the floodplain running green to the horizon. At Nourlangie the walk under an ochre-streaked wall reaches the Anbangbang Gallery, painted and repainted over thousands of years. Namarrgon the Lightning Man stands there with stone axes strapped to his head, elbows and knees, the ancestor the Bininj hold answerable for the storms of the build-up, striking those axes against himself to split the sky.
Yellow Water, Ngurrungurrudjba to the Bininj, carries roughly a third of all Australia's bird species and saltwater crocodiles at a density few places match. The cruise boats are flat-bottomed, so they take you off the open billabong and into side channels where paperbarks stand in the water and lilies close over the bow. At that range you are level with the birds rather than above them, and a crocodile on the bank is a few metres off the gunwale. From January the monsoon sends Jim Jim over the escarpment in a single drop of up to 200 metres; by mid-year that cliff is dry rock. What the wet leaves behind is the plunge pools at its foot, checked by rangers and opened for swimming, the only way you get into the water in country like this. And on the wall beside the main gallery at Ubirr, which anyone walking the loop goes past, is a thylacine, painted by someone who still had the animal in front of them.