Squealing children crowd a log jetty festooned with scrap fabric bunting, as our skiff boat, flanked by a flotilla of dugout canoes with fluttering palm fronds for sails, floats into a flooded caldera.

Bleary-eyed but excited, the residents of Garove Island have been awake all night celebrating an important arrival.

On this occasion, we're not the guests of honour; that privilege has been afforded to a statue of the Virgin Mary, currently touring the islands by helicopter.

Adorned with a necklace of pig tusks, she sits at the head of a wooden church, where worshippers kneel piously on pews beneath heart-shaped mobiles fashioned from chicken feathers.

Beyond being a religious icon, she represents something arguably more powerful: contact with the outside world.

Apart from religious missionaries, this remote coastal village in Papua New Guinea's Witu Island Group rarely receives visitors.

I'm travelling with Australian-based Coral Expeditions, one of the few cruise companies who lead tours along the coastline of this culturally and biologically diverse southwest Pacific country, made up of a mainland and several islands.

There are more than 800 recorded languages, tribes and political systems in Papua New Guinea (PNG), all equally colourful and exotic.

Over the course of 10 days, we'll visit 16 locations from the comfort of the 72-person Coral Discoverer, offering a higher standard of accommodation than is currently available on land.

All our food is carried on the ship and seawater is cleaned through a filtration system. For many, it poses a safer, more reliable - but no less adventurous - way to explore.

Curious spectators flock around our vessel, balancing in canoes that seem impossible to keep upright (I learn the wet way when I'm invited to clamber on board).

A pale-faced European sat opposite a cocoa-skinned child with a brilliant blond afro - we stare at each other with the same wide-eyed fascination.

Missionaries no longer pass by the remote village of Bun on Tolokiwa, part of the Bismarck Archipelago, and our 7.30am landing on the black sand beach is the first by any foreigners in two years.

Beating kundu drums herald the start of a classic sing-sing (a typical ceremonial performance of song and dance), played by chanting men with glistening, muscular bodies. A procession of Siassi women sashays through the dust, pig tusks curled around their naked breasts and rainbow-dyed palm fronds splaying from rears like tail feathers.

Disguised by a mass of dried banana leaves, one dancer leaps and swirls towards the audience, his pig skull mask sending terrified wild boar (and tourists) scurrying for safety beneath stilted bamboo huts.

Of course, villagers don't spend every day dressed in grass skirts and war paint, but dance and music is still a vital part of their culture.

More unusual shows greet us when we arrive in Bien, a 400-person village set amid sago swampland on the mighty Sepik River, back on the mainland.

Levels of humidity reach a stifling level as we drift through clumps of water hyacinth in the muddy river famous for its scarification ceremonies, where razors are used to make decorative skin markings and initiate young men into the clan.

Bouncing sunlight in multiple directions, several battered DVD discs are suspended from trees as welcome decorations, and I conclude there could be no better use for Shrek or Harry Potter.

A girl with a squawking parrot on her shoulder takes my hand and leads me to the village centre.

While singing about hornbills and geckos, a group of sniggering school children performs a bizarre slapstick dance, waddling under the weight of giant rice sacks daubed with pictures of fat westerners.

"I think that might be about you guys," smirks our expedition leader, Steve.

Further demonstration of the PNG sense of humour is a cross-gender comedy sketch, where most laughter seems to stem from a young man with lopsided, cone-shaped boobs.

Oddly, it's the first of several similar shows we witness on the trip, leading one amused passenger to remark: "This is the only place where I've seen more men in bras than women."

According to our guest lecturer Dame Carol Kidu, who was once leader of the opposition party in PNG, slapstick drama has been used extensively as an educational tool.

An Australian who married a Papua New Guinean, Carol provides a fascinating insight into tribal society from the perspective of an outsider.

"I not only married a man; I married a whole clan," she confides.

A self-described "minister for odds, sods and lost causes", Carol is now retired from politics but still works hard to improve women's rights in a place where the birth rate is unfeasibly high (nearly half the population is under 18) and contraception is still considered taboo.

A tattoo of three bands around Carol's wrist is a symbol of her continued commitment to the culture. "My two granddaughters begged their mother for marks," she explains. "It gave them a sense of identity."

Along with fire-starting and sago-making, we watch a traditional tattoo demonstration in a rainforest clearing at MacLaren Harbour, in the Tufi Fjord. These are all customs which would likely disappear were it not for tourism.

Sat on outriggers, we drift through a tunnel of tangled mangrove roots, transfixed by the sound of paddles slowly splicing through water.

Wearing thick, wiry afros decorated with pink hibiscus flowers, our strikingly attractive female rowers look like the stars of a Seventies Blue Note album cover.

Soon after disembarking, we're ambushed by a group of "savages" painted head to toe in black with acid pink tongues. ("Brian", one of the lead actors, later poses for photographs.)

Although unintentional, it's an ironic reminder of the misguided prejudice so many outsiders have about Papua New Guineans being uncivilised.

Tufi people are famous for their headdresses, and villagers have clearly pulled out their finest feathers for our arrival. One elderly man has six different plumages on his crown, many taken from the celebrated Birds of Paradise. A cuscus tail trailing the nape of his neck makes him look like a South Pacific Davey Crockett.

It's tempting to pass judgment on his choice of dead animal attire, but the headdress is a 15-year-old heirloom, carefully dismantled and wrapped away after each ceremony, and passed down through generations.

In a bid to make customary practices sustainable, the government has banned all shotguns and hunting is only permitted with spears.

Papua New Guinea is just as vibrant underwater, as I discover on numerous diving and snorkelling trips along the pristine fringing reefs.

Offshore from Dobu Island, close to the Dei Dei Springs, I snorkel through bubbling hot vents in the clearest water I've ever seen.

It's a magical experience, which befits the region's reputation for sorcery and hocus-pocus.

Although essentially rows of simple shacks, streets are immaculately clean, with not even a toenail clipping or globule of bettlenut spittle carelessly discarded, for fear they might be used in casting spells. I'm left wondering if it's a clever government ploy to keep the place tidy.

Flourishing with rosebuds and other incongruously twee plants introduced by missionaries, gardens are meticulously well kept. People clearly invest great time - and care - in what little they have.

In a place so far removed from the modern world, it's all surprisingly familiar and actually, contrary to popular belief, rather civilised.

TRAVEL FACTS

:: Sarah Marshall was a guest of the Papua New Guinea tourist board (pngtourism.org.uk) and Coral Expeditions (coralprincess.com.au). The 12-night Cairns to Rabaul cruise costs from 10,250 AUS dollars pp (two sharing) - around £5,500 - including all meals and excursions. Departs October 4, 2017.

:: Cathay Pacific (www.cathaypacific.co.uk; 020 8834 8888) flies from London Heathrow to Cairns from £679 return.