Why Kimberley is one of the world's hottest places to cruise this year

There's a moment early in my trip when I consider dunking myself into the sea quietly, just to swim for a second. The sun's setting over a distant, lonely coast, and the sea's the colour of apricot jam. Though we're at anchor on the open ocean, it's as still here as a lake. Then the lights by the back deck switch on with the dusk and - beneath the water - I count five sharks ... no, six, seven, eight ... more. God knows what else lurks below: saltwater crocs, box jellyfish, giant squid? The Kimberley coast is no place for the faint of heart (or snorkellers).

Located in far north-west Western Australia, the Kimberley is one of the world's most inaccessible destinations. It's an area more than twice the size of Great Britain, and it's home to just 38,000 people, about half of whom are Indigenous Australians. But because there are hardly any roads here (for there are very few towns or resorts), the only way to see its coastline is by ship.

Which is why the Kimberley is considered the grandest prize in Australian cruising, primarily for domestic travellers (the inaccessibility of the region stops all but the most intrepid international cruisers). No wonder, the Kimberley is Disneyland and Disneyworld combined for the cruiser kind - an almost entirely unoccupied wilderness that's accessible only to us who visit by ship.

I'm here aboard Le Laperouse, Ponant Cruises' staple Kimberley vessel. I'm travelling from Broome to Darwin over 11 days, though I could've done it in reverse. The maximum passenger load for this vessel is 180. The Kimberley region is the domain of smaller passenger ships (with higher staff-to-guest ratios), primarily because the region is protected by the Southern Hemisphere's fiercest tides, which can be as high as 14 metres. Added to its inaccessibility for things like food supplies and the fact any medical emergency requires a long helicopter flight, big cruise liners don't cut it up here. But small-ship cruising is growing in popularity each year, with more and more new companies coming to cruise here for the first time (see page 29).

Looking around on deck, the majority of passengers seemingly got the memo that our expedition is as much about excursions by zodiac through croc-infested waters as quantity time at the dinner table. While most look 60 or above, they're mobile, they wear binoculars around their necks and are in hiking pants which zip off at the knee.

Broome is a hell of a place to depart from, especially in this magic hour before sunset. The red ochre of the outback collides with the bright green waters of the Indian Ocean, though as we steam north my focus is distracted by endless pods of humpback whales, which take turns to breach. The Kimberley is home to the world's largest population of humpback whales: approximately 35,000. Between June and October, these waters are the site of the world's largest humpback whale migration, as they swim north from the Antarctic to calve.

At night, away from the lights on the top deck, a billion, bulging stars shine down from the cosmos. I wake early with the dawn - I love these quiet times on ships before breakfast - and the coastline beside me changes from open woodlands and flat buttes to harsh orange-brown plateaus and back again, all in a few minutes.

But it's the offshore islands that typify the Kimberley's landscape. More than 30 per cent of Australia's 8222 islands are scattered along the coastline, and my itinerary revolves around exploring as many of them as we can. The delicate nature of the environment makes it impossible to land on some of them, like here at the Lacepede Islands which we anchor off after breakfast. Instead we travel in zodiacs closely along the shore as green turtles pop up beside us in one of Australia's most significant turtle breeding grounds, and estuarine crocodiles patrol the mangroves.

My days are spent on shore excursions - broken up by long, luxurious lunches - or on the top deck steaming between destinations, always in sight of the shore. Barely born humpback whale calves and their mothers can be seen everywhere as we pass through North Lalang-garram Marine Park.

Further north-east, as we enter the isolated Bonaparte Archipelago and its long maze of islands, ancient rock art becomes the focus of our shore excursions. We stop at places such as Jar Island in Vansittart Bay to see the oldest detailed depiction of human figures on Earth. The oldest rock art discovered in the region is about 40,000 years old, mostly in rock shelters or on flat rock expanses. I climb high into a network of caves, sometimes crawling on my back to see the least accessible ochre paintings. After the art show, we find deserted beaches to stroll on and find the tracks of huge estuarine crocs by the water (some as large as five metres long). Even beside the clearest and shallowest water, guides warn us to keep back from the edge.

While there's certainly no swimming, I manage to get wet at King George Falls, Western Australia's highest twin waterfalls. We anchor where the King George River meets the sea and take zodiacs 13 kilometres to the falls. The landscape here is approximately 1.8 billion years old - sandstone gorges rise up 100 metres from the water. The further we go, the taller the sandstone cliffs, till we're dwarfed on all sides, facing the 80-metre-high waterfalls. My guide directs the zodiac to the bottom of the waterfall, till the downpour hits the front of the zodiac and I can dip my entire body beneath the rush of water with no fear of crocs.

Though I'm travelling through the peak of the Kimberley cruise season (midwinter), in 11 days I see just four other vessels. We only anchor near one ship, just for a night (like magic, it's gone when I wake in the morning). In a wilderness this vast, it's easy to find your own patch. Provided you don't mind sharing with the saltwater crocs, the bull sharks and the jellyfish.

THE SHIP: Ponant's Le Laperouse

THE SIZE: 131 metres long, 92 cabins, 184 passengers

GOOD TO KNOW: Cruises include all meals, an open bar (including Charles Heidsieck champagne), free Wi-Fi and excursions, while prices for everything else (such as spa treatments) are in Euros.

GET ON BOARD: Ponant offers 11-day expedition cruises between Broome and Darwin from June to October. Prices from $12,810 per person.

EXPLORE MORE: au.ponant.com

The writer was a guest of Ponant.

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