Where monsters meet: Nature sets the rules on this island in Vanuatu

The monster introduces itself with a rumble so low that it seems like a growl from the depths of the earth. We stop our four-wheel drive to listen, a welcome pause after nearly two uncomfortable hours bumping along a rugged, unsealed road through fields and dense, sticky tropical forest. And then the thick vegetation ends abruptly, revealing a barren plain of grey ash stretching ahead. And at the end of that stark plain: the monster, the volcano, Mount Yasur on Tanna Island in Vanuatu in the South Pacific.

We make a beeline for the volcano, and the growls grow louder. I find myself more delighted than shocked. The monster ahead stirs a sort of monster I sometimes find inside me. It's a beast that craves raw experiences. There is an unspeakable thrill in facing something as awesome as an active volcano. It makes me feel the grandness and the power and the majesty of nature. It brings home our human vulnerability.

Mount Yasur is often said to be the most accessible active volcano in the world. I pay obeisance to its grand presence among a motley group of two dozen people, including volcanologists, French families with young kids, and adventurous honeymooners from England. During the pre-climb briefing, they all - we all - are flush with excitement.

And then, the ascent itself.

Drifting ash, lots of it, sticks to sun-screened faces. It turns our hair grey like a bad Instagram filter. For some nervous reason, we all laugh. Less amusingly, it burrows into every crevice of my camera equipment. But even this is worth it as we reach the lip of the caldera, the basin formed when a volcano erupts and collapses. Smoke and steam billow in enormous plumes before our eyes, accompanied by giant rafts of embers that dance their way upward in a sky which is growing darker as the sun sets.

We all pause on the soft edge, quiet and incredulous that we are so close to the fire below. We all seem to be waiting for the same thing. We hold our breath and the volcano holds hers. Then it finally happens: a spray of erupting red into the darkening sky.

Each time the monster belches, we lean over the edge as far as we dare. It feels like the breath of a dragon on our skin. It's impossible to be unmoved. When your internal monster encounters a monster of this magnitude, a kind of visceral chemistry takes place. Like the foolish beasts that we are, we have to stay and watch the true monster.

That, without any doubt, is the highlight of my trip to Tanna Island. But there are other delights. Where else can you go scuba diving on coral reefs in the morning, then climb an active volcano in the evening? During the day, the coral cover at Tanna's Circus Reef is impressive but so is the island's famous Blue Cave. A short boat ride up the north-western side of Tanna takes you to the mouth of the underwater grotto, which is easily accessible to both snorkellers and scuba divers. The cobalt-blue, crystal-clear water is a pleasant 24 degrees. It is easy to slip a couple of metres under the lip of the rocky overhang to find what seems like an aquatic cathedral stretching up to a gap which lets in the light from the sun. It is an ethereal experience to float on my back in the warm seawater and gaze upwards at the trees in silhouette.

Our accommodation is at the White Grass Ocean Resort & Spa, which is setting up a marine-protected area in the waters off Tanna, says its manager David Perry. Ecotourism is the growing market that the resort wants to serve and its dive operation, Volcanic Island Divers, is the first PADI Eco-certified dive resort in Melanesia.

The big attraction on the brochures may be the amazing natural wonders but the island's people, too, are a drawcard. In Yakel village, chief Alby welcomes arranged visits but tries to preserve traditional custom - or "kastom" as it is called. He favours the local language and does not speak Bislama, one of Vanuatu's three national languages (along with English and French). Among the prized possessions he shows us are photographs from a 2007 trip to England to visit the royal family.

Afterwards, we cool off by being pounded by massive sheets of water at the Louniel Waterfall, before making our way to nearby Louniel Beach, where I spot a group of guitarists walking in single file along the shore on their way home after band practice. Their colourful instruments and attire belie their shy demeanour but make them impossible to ignore against the black-sand beach.

By the side of the main road, we come across groups of men sitting languidly at a nakamal, or kava bar. Out the back of the bar, boys are paid to process ground kava root through cloth using water, which the men drink out of coconut shells to relaxing effect.

That is all very pleasant to observe but my jaw really slips off its hinges when I spot a colourful mural boldly stating "Welcome to Will Smith" - a tribute to the actor after he filmed part of his documentary series Welcome to Earth at Mount Yasur.

Covered with ash, salty from diving, and hungry, I return to the resort, set on the island's rugged western coastline. Seafood is a highlight on the restaurant's menu, with the poulet fish, a tropical snapper, and lobster being my firm favourites. Best of all, there are multiple vantage points to take in the last of the day's colours from the resort's high seaside position.

Read more on Explore:

At the end of the day, you have to choose what kind of trip you are looking for. Do you want it to be curated and predictable? If the answer is no, and you're willing to work a little bit for the payoff, then Tanna allows you to be an unedited version of yourself, immersed in the natural world.

Humans have rocketed to the moon, plunged to the depths of the ocean, and scaled the highest peaks. But as I stare into the mouth of the caldera at the burning belly of the beast, I am left with the thought that here is a place on Earth that we will never conquer.

Getting there: Air Vanuatu flies from Sydney and Brisbane to Tanna via Port Vila, see airvanuatu.com

Staying there: White Grass Ocean Resort & Spa is close to the island's airport and has an in-house restaurant, bar, spa, outdoor pool and scuba diving operation. It also offers excursions, including to the volcano. Accommodation is offered in tasteful island bures configured for couples or families. The writer stayed in a double ocean-view bure, which starts from $365 a night, see whitegrasstanna.com

Explore more: vanuatu.travel/au

The writer travelled courtesy of Whitegrass Ocean Resort & Spa and Air Vanuatu.