I made a promise to paradise in Palau and now it's stamped on my passport

In an island nation so pristine that visitors must sign an oath to protect it, Amy Cooper takes the pledge.

Palau's message is clear right from the start. This experience you're about to enjoy in a gorgeous, unsullied island paradise? It's a two-way thing.

The thunk of a proper, old-school arrival stamp (so much more soulful than a Smartgate) fills almost a whole passport page with words that cut through my post-flight fug with their quiet dignity:

"I take this pledge as your guest, to preserve and protect your beautiful and unique island home.

I vow to tread lightly, explore mindfully. I shall not take what is not given. I shall not harm what does not harm me.

The only footprints I shall leave are those that will wash away...'

Bravo, Palau. In times when souls are sold for the tourist dollar, this nation in the remote western Pacific asks all visitors to say I do on the first date by signing the Palau Pledge as a condition of entry.

Introduced in 2017, the pledge was the first of its kind, and has since been signed by the likes of Leonardo di Caprio and the Rolling Stones - a big, bold statement for a tiny country.

On a map, Palau's a crumb on a giant blue tablecloth. Around 900 kilometres south-east of the Philippines, 1295km south-west of Guam and 1850km north of Papua New Guinea, the Micronesian archipelago has only sea and sky for company.

Getting there from Australia has until now been a circuitous schlepp, but direct flights have debuted and now the country with the tagline "pristine paradise" is just a six-hour hop away.

What's waiting there? Oceanic utopia, says a diving friend whose favourite watery haunt anywhere on earth is Palau's Rock Islands Southern Lagoon, a UNESCO heritage listed archipelago-within-an-archipelago where hundreds of uninhabited limestone islands form lakes, lagoons and caves.

Even from above as we descend, I can see why.

Wow. It's like gazing into a lava lamp. The island chain undulates in a luminous flow of globules and swirls, jade on radiant aquamarine, as if lit from somewhere deep beneath. And all around it, blue forever, as if there were nothing else in the world.

Palau is largely liquid. A diminutive 460 square metres of about 300 islands is dwarfed by surrounding ocean territory 1000 times larger. Put simply: land roughly the size of Adelaide, sea slightly bigger than France.

With 19,000 people, it's also the world's fourth smallest country, population-wise. Palauans inhabit just nine islands within a giant coral lagoon encircled by barrier reef. They're drastically outnumbered by one of the planet's densest and most diverse concentrations of marine life - an ecosystem so extraordinary it's been dubbed the "underwater Serengeti".

We're talking at least 1450 fish species, 550 coral species, 50 species of sharks and rays, and eight of the world's 12 species of giant clams.

Custodianship of these treasures is a hefty responsibility, and Palau doesn't flinch from it. Since 2015, 80 per cent of its waters have been designated the Palau National Marine Sanctuary, one of the planet's largest marine protected areas. In 2009 Palau became the world's first national shark sanctuary. There are further laws protecting dugongs and various vulnerable fish and mammals, making this little scatter of land and its mini populace a mighty global conservation force.

Early on our first morning, I fling back the curtains in our hotel in Koror, Palau's busiest town and gateway to its watery kingdom, and a tide of sunlight and sapphire floods the room. The marina is already awake; divers and snorkellers are loading gear onto boats, their anticipation infectious, as if they're heading to a party out on the gleaming blue.

I'm eager to join, but our first deep dive will be on dry land - into Palauan culture.

As we travel to Airai village on the main island, Babeldaob, our guide Velma explains that Palauan traditions have endured over millennia. She's about to show us where the story begins.

Velma wears the Palauan women's traditional woven hibiscus bark skirt dyed in clan colours of purple, flame, gold and scarlet. Along a path of ancient stones, she leads us to an imposing canoe-shaped timber building with a steep thatched roof soaring some 12 metres high.

The bai, or chiefs, meeting house, was constructed arbout 200 years ago without metal tools or parts, the giant ironwood frame secured only by coconut fibre rope and skilled design. Intricate paintings and carvings of animals, symbols and figures cover the beams and walls.

Their meaning is far deeper than decoration, says Velma. They're motifs from a vault of stories passed down over centuries in the oral tradition: cautionary tales, inspiring sagas, local history, spiritual lore. Together, they form a roadmap for life based on a central value: conservation.

A Palauan origin tale tells of a greedy giant devouring the islands' precious resources. After the ancient Palauans destroy the giant, they build bais throughout the islands as guiding lights for living in harmony with nature.

Since then, Palau has faced down many more greedy giants. From the 19th century to independence in 1994 the country was colonised successively by Spain, Germany, Japan and America.

Palauan culture came under assault. Most bais were destroyed by enforced neglect or during World War II, when the islands were a bloody battleground in the Pacific Theatre.

The knowledge, however, remained. Now the handful of surviving bais, as well as new ones built in the old style, are once more the engine rooms of Palauan society; a sacred space, a base for the Council of Chiefs, and for imparting traditional skills such as fishing, boat building and carving.

Conservation, embodied by the bai, still defines Palau. "It symbolises everything about our culture and what it means to be Palauan," says Velma.

Just outside the village, in a fertile tapioca plantation, we join some of Airai's senior women to harvest our lunch. Subsistence farming in Palau, using organic methods unchanged over generations, is traditionally women's responsibility while men go to sea to fish (and, in former times, to wage war with rival clans).

Talk of gender roles can ruffle an urban feminist. But Palau's rules are very different from ours, the elders tell us.

As they show us how to pound the tapioca before shaping it with coconut oil into dumplings to be steamed golden, the women explain Palau's matriarchal society. Women control land and finances. Family wealth and status pass down the female line. While the Council of Chiefs is male, they're appointed - and removed - by another council of formidable matriarchs.

"Like a board of directors?" I ask one of our hosts, Marygold. She smiles. "More powerful."

Motherhood, planting and cooking are the highest-status work. When a mother has her first baby, she's pampered with steam treatments and healing oils, then feted in an exuberant ceremony.

Women's influence is real. Although Palau now has a US-style elected government, the Council of Chiefs guides their decisions - and we know who guides the chiefs.

The female-run Experience Airai tours, sharing village life, crafts and traditions, aren't just for visitors. They teach local youngsters the same skills and values, increasingly important when overseas work and study call new generations away.

Are there still enough matriarchs here? Yes, the elders say. Younger Palauan women find ways to combine modern careers with traditional responsibilities. Like women everywhere, they know how to juggle.

"It's important for us to balance progress with preserving our culture," says Velma. "What's most important is that the knowledge is kept alive."

Until recently, she adds, visitors tended to interact only with Palau's ocean, passing through without gaining any sense of its custodians or their traditions. These tours aim gently to amend that and have proved immensely popular since launching in 2019.

It's easy to see why. Time with these warm, wise and funny hosts makes a great day out, but also adds an essential backstory for your marine adventures. And before taking the plunge into their beautiful blue backyard, it seems only right to have the matriarchs' blessing.

Our boat speeds out of Koror through a maze of forested islands sculpted by time and tide into fantastical architecture: mushrooms, umbrellas, cupolas. Some Rock Islands seem to hover over the water. Others break the surface like heads crowned with unruly green hair.

Apart from occasional vessels, this enchanting landscape is blissfully human-free. But it teems with other life.

In a hidden marine lake formed 12,000 years ago on Eil Malk Island, we snorkel among harmless golden jellyfish found nowhere else in the world, their sting evolved away by predator-free millennia. They drift through sunbeams like delicate little ghosts.

Back out in the lagoon, we snorkel amid slopes thicketed with gold-hued staghorn coral in underwater forests at Clam City, home to the world's largest living marine bivalve. In water as transparent as air we marvel at the giant Tridacnas clams, some 200kg and more than a metre long, their fluted shells lined with vivid blue inner mantles, like flamboyantly frilled petticoats.

At Ngermeaus Island, black-tip reef sharks glide close around us, eyeing us idly, each with an escort of cleaner fish providing a mobile spa.

We kayak within Nikko Bay's cathedral-tall limestone edifices, paddling through glassy cerulean lagoons into a fairytale cave where fruitbats flutter above. These waters shelter a riotous rainbow garden: basket and brain corals in super-saturated pinks, reds, oranges, greens. "They call this Disney Lake," says Quincy, our guide from Fish n' Fins, but the Little Mermaid could only dream of digs like these.

All those centuries of conservation show in fearless, thriving marine creatures and crystal waters. We learn how protecting Palau's oceans began with the "bul" tradition, in which chiefs would prevent fishing to allow the ocean to thrive. The National Marine Sanctuary enshrines those ancient ways into modern law.

With every flipper stroke, more magic unfolds. In endless marine neighbourhoods, we encounter hawksbill and green sea turtles, manta rays, leopard fish, humphead wrasse, lemon and black striped Moorish idols, clownfish, groupers, huge shoals of little silver fusiliers moving as one, and my favourite - the extrovert rainbow parrotfish with their candy-store colours.

We discover, too, that despite Palau's fame as a diving destination, there's plenty to see by snorkelling alone. Shallower spots on the inner reef are in fact best explored that way and others, like Jellyfish Lake, are snorkel-only zones. Over seven days, we see endless riches - from reefs to wrecks - without ever donning tanks.

Day after day, time dissolves as we drift through alien, enchanting landscapes, floating in current-free blue, following rhythms set by sun and tide. When it's time to step back onto land, it's like waking from a dream.

Koror Solid Waste Management Office doesn't have quite the same ring to it as Jellyfish Lake or Paradise Reef, but it's just as precious to Palau's ecosystem.

Here, Palau's ocean life lives on land in all its lovely shapes and shades, this time rendered in glass. In a neat piece of circular symmetry, some of that glass is ocean-borne, too. Gathered in beach clean-ups as well as residential recycling, and in the skilled hands of Palauan glassblowers at Belau Eco Glass, the sea's detritus becomes its friend.

Buying a keepsake clownfish, ray, shark, dugong or coral made from recycled glass (Corona beer bottles are the perfect shade for the rockstar golden jellyfish) supports Palau's conservation efforts, and you can deepen the connection further by creating your own.

With plenty of instruction from my teacher, Sochai, who started out working in the collection department before graduating from the centre's glassblowing training program, I learn how to blow and turn a molten blob into a glass tumbler in pinks, yellows and blues - inspired by my favourite rainbow parrotfish.

Behind the scenes, there's lots more happening. The centre recycles multiple materials - including PET, steel and aluminium bottles and food waste - and converts plastics to fuel.

The project's director, Katsuo Fuji, is excited by what this means for Palau's future, and the planet's, too. "We believe we can make it possible to realise the world's first national circular economy system."

In one elegant stroke, this enterprise solves recycling conundrums, creates careers and helps visitors keep those Palau Pledge promises.

Another is the woodcarving workshop at Tebang Woodcarving, with master carver Ling Inabo, who tells us how stories from the bai are carved in low-relief onto individual wood planks. Like books, they can travel out into the community, perpetuating their ancient messages. Ling is very kind about my effort, a shark with too many fins and a smile (he's a happy shark, because he lives in a sanctuary).

In the evenings we kick back in bars and restaurants around the water's edge, where marine scientists, holidaymakers and locals alike all wash up after blissful days at sea. There's live music and bonhomie, tales of marine marvels.

It's an unavoidable question: could tourism be the next greedy giant? The Palauans have already considered this. The Pledge came about after a 2015 record influx of visitors - more than seven times the country's population - many of whom "didn't understand how to care for the environment", says one of our guides, diplomatically.

Now numbers are carefully capped at sustainable levels, and marketing is aimed at those who appreciate and respect the Palauan ecosystem. Australians are considered such visitors. Our Great Barrier Reef Foundation collaborates with Palau in the Resilient Reefs Initiative, and Byron Bay now has its own pledge (alongside Hawaii and New Zealand), inspired by Palau's.

'We hope more of you will come," says one of our new friends as we prepare, reluctantly, to leave.

At the airport, I read the Pledge again. Really, those vows were an easy ask. Riding the gentle slipstream of Palauan life, you're a participant rather than just an observer, welcomed by your hosts into a story as old as the islands themselves. These precious waters, lands and creatures will speak to you, as they have to generations of Palauans, calling you to cherish them.

Abiding by the Pledge, I'm taking from Palau only what was given: my wonky shark, pretty parrotfish tumbler, and some impressive new skills with tapioca.

I'm also leaving with optimism. If such a tiny nation can be so powerful a force for good, perhaps the future's brighter than we think.

Getting there: Nauru Airlines has a weekly six-hour direct service, the Palau Paradise Express, offering nonstop flights from Brisbane to Palau. Fares from $2080 return. nauruair.com

Staying there: Palau Royal Resort, right on the water in Koror, has 157 rooms and suites, a private beach, swimming pool and beach bar. From $265 per night. Cove Resort, also waterside in Koror, has a pool, garden and bar/restaurant. From $279 per night. palau-royal-resort.com; coveresortpalau.com

While there: Snorkelling, padding and diving tours are available with Neco Marine, Fish & Fins and Paddling Palau, and workshops with Tebang Woodcarving and Belau Eco Glass. For an authentic cultural experience, the Experience Airai Tour is a must-do.

Explore more: pristineparadisepalau.com

(intro) Eating local produce is one of the easiest - and tastiest - ways to support Palau's sustainability. And it's as fresh as it gets - most restaurants use ingredients grown or caught by family members the same day.

Market

The bi-weekly 680 Night Market is the perfect entrée to a Palauan feast. Vendors sell home-grown and home-cooked treats, there's traditional music and dancing on the main stage, and locals turn out in droves to shop and mingle.

Fish

Fished only by locals, Palau's oceans nurture spectacular seafood. Staff at Drop Off Bar and Grill can tell you who caught your meal that day. Look out for fresh blackjack, opakapaka, river snapper and tuna.

Ukaeb

Light but decadent fresh minced crabmeat drenched in creamy coconut milk and served in the shell. Try it with a sunset backdrop at Elilai Seaside Dining, right on the waterfront.

Billum

Tapioca - or cassava- mashed and mixed with coconut milk and flesh, with seasoning, wrapped in its leaves and steamed until golden.

Demok

Palau's national soup is a nourishing brew of green taro leaves, coconut milk and land crab with local herbs and spices - a delicious post-ocean pick-me-up.

Fruit

Breadfruit, banana, soursop, cantaloupe, passionfruit, star apple, bilimbi and many more including the ubiquitous coconut (remember, it's a fruit) - Palau is a bottomless fruit bowl of sweet, succulent delights.

Beer

Wash it all down with Red Rooster beers, brewed only in Palau using pure, tropical rainwater.

The writer was a guest of Palau Visitors Authority.