Our guides are Rod, a "white fella" from Melbourne, and Samson, a local Aboriginal with a lovely smile and a beautiful, gentle manner. They take us to the little museum, which is full of depictions of Dreamtime myths and yellowing photos of Catholic nuns in white habits, their curly-headed charges lined up in rows.
It's clear from listening to Samson that the social bonds in this community are tight and traditional. There are four clans or "skin groups" on the island - Mullet, Sun, Pandanus and Rock - and only certain ones can intermarry. Samson, who is from the Pandanus skin group, tells us: "If I marry someone from the Pandanus clan, I get into big trouble."
The island is teeming with creatures and the local people eat carpet snakes, sea turtles, mussels, mud crabs, bream, barramundi and crocodiles, among other things. I ask Samson what he had for breakfast. "Weet-Bix," he says with a grin.
We drive to another part of the island for morning tea. An elderly gent called Teabag is making damper and is reluctant to tell me his real name. I later discover that it's because he shares his name - Fabian - with someone who recently died and local tradition has it that the name must not be spoken for two or three years, when the departed's final ceremony has been conducted.
Now we meet four "Tiwi ladies": Marcella, Maryanne, Maria and Phillippa who are sitting on the ground weaving. They are shy but friendly, and introduce themselves before painting their faces in preparation for the smoking ceremony.
Ironwood leaves are placed over a small fire and the smouldering twigs are waved over each one of us in turn to chase away bad spirits - with Christian prayers.
"May the Lord bless you," Marcella murmurs to me and I find myself brushing away tears. This is not quite the "culture from the bus window" response I was expecting to feel.
Then the women and some of the men perform their totem dances: shark, buffalo and crocodile, which are slightly intimidating animal action songs, and I regain my composure.
Next we visit a couple of arts centres and watch the artists at work. There is an enormous market for "Aboriginal art" and I have no idea whether what they are producing here is based on tradition or commerce. I was told the day before that dot paintings only go back to 1971, when artists exchanged traditional methods for dots as a way of disguising their sacred stories so Europeans couldn't understand them.
Here, the artwork seems the opposite - easily recognised symbols from nature for the indigenous art aficionado. Whatever the truth, the results look pretty accomplished to me.
Whether you would find these cushion-cover motifs smeared onto ancient Aboriginal rock walls is another question.
I get the chance to find out the next day, when I travel to Ubirr and Nourlangie in Kakadu National Park back on the mainland. These are two of the best "galleries" of rock art in Australia and contribute much to the park's World Heritage status as an area of significant cultural as well as environmental importance.
The paintings here crackle with history and folklore: "mimi spirits" and other creation ancestors swarm over jutting rock faces. The simple outline drawings map changes in the landscape over thousands of years, including the coming of Europeans.
But the age of the paintings isn't that important to the local people: it's the act of painting that puts them in touch with their ancestors, and many older paintings are covered up with new ones.
A bit of detective work can be helpful, though. One painting at Ubirr depicts a figure with a boomerang - something that hasn't been used in the Northern Territory for 15,000 years. Another painting is of a thylacine or Tasmanian tiger, a species that has been extinct for more than 4000 years.
Some paintings are ancient morality tales. There's Mabuyu who warns against stealing. He can be seen dragging a barramundi on a string but then a greedy hunter cuts the string and steals his fish. Mabuyu tracks the thief to a cave and rolls a rock over the entrance so that the entire clan dies of starvation.
At Nourlangie in the Anbangbang Gallery, a dangerous spirit called Nabulwinjbulwinj eats women after striking them with a yam, although I'm not sure whether the lesson is to stay away from spirits or yams.
A short distance away, the teaching is more obvious. Namarndjolg and his sister have broken the incest laws and Namarndjolg is tied to a tree and set on fire. He escapes into the river and becomes Ginga, a great saltwater crocodile. (As with the Tiwi Islanders, she wasn't a sister in our sense of the word but a member of his skin group.)
The galleries and the paintings themselves are beautiful, set in rocky outcrops that offer extraordinary views over the surrounding countryside.
Here, it's the memory of people that remains. However simple their material lives - and those of their modern descendants - appear, they are still spiritually in a whole other world from us. We are privileged to see these secret stories. It occurs to me the artists back on Bathurst Island have it all worked out. They are producing pretty pictures that the white fellas can understand and keeping the really meaningful stuff for themselves. With that strength of community, they'll be okay.
Getting There
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