As the passage narrows to a two-metre gap, the claustrophobia intensifies. What started out as a bounding abseil down from normality to the netherworld has become a case of gingerly feeding the rope and hoping not to shred skin on the jagging, threatening rocks. From the surface, the landscape around Waitomo doesn’t look all that hard-core. It is a scene of gentle prettiness; of rolling green hills that may well play host to a Hobbit house or two.
But time and nature have wrought havoc underneath the surface of New Zealand’s North Island and the pretty wildflowers growing on the grassy contours disguise an elaborate system of caves.
Getting down into them requires a 35m shimmy down a “tomo”, a hole in the ground that acts as a vertical gateway to the subterranean world. After negotiating the narrows, it’s a case of tumbling rapidly into the void.
Once landed inside the cave, the adventure becomes even more peculiar, with a flight of faith on an under-ground zip line. You clasp the dangling handle, with legs raised in the air, then a push from behind sends the trusting victims off into the darkness. There are no lights, no torches and no clue so as to where the journey will end.
The halt is abrupt, but lights suddenly flicker from behind and reveal that we’re on a ledge above the Waitomo river. It has carved its way underground over the centuries and the way out is to follow it until it breaks free of the cave system.
Large rubber inner tubes are handed out and it’s made crystal clear that there’s no dignified exit here. We’ve got to semi-sit in them, then leap over the edge, landing in the water with an enormous splosh.
The water, denied access to sunlight by the cave roofs, is fiercely cold. Slowly paddling downstream with the hands becomes a test of tolerance, with every finger-dip in the river provoking an involuntary yelp.
But for the creatures we’ve come to see, the temp-eratures seem just fine. The torches are switched off, but this time the darkness is broken by thousands of tiny lights, speckled across the walls and the roof of the cave.
The lights are alive – they’re glow-worms, which is a rather romanticised name for what they really are. A type of maggot, they dangle down spider-web-esque tendrils to catch passing flies. And, frankly, the farther you go into the details of their life cycle, the more horrible it becomes.
But if you just lie back in the tube, and take in the twinkling display unfolding all around, the finer details are irrelevant. It’s like being alone under a perfect night sky, the moment enveloped in a spellbinding, ethereal beauty.
The glow-worm caves at Waitomo are far from alone in terms of spectacular weirdness on New Zealand’s North Island. The South Island may be the one packed with the sort of natural beauty that turns most visitors into awestruck, stammering simpletons, but if it’s the unusual you’re after, the North Island is absolutely heaving with it.
This isn’t always a gift of the natural environment, either. Sometimes, it just takes a moment of inspiration – and that’s what struck a local farmer when the Stratford to Okahukura railway line closed down in 2009.
With no trains going down it, he enquired about leasing the line. When the answer was positive, he bought some golf buggies and adapted them so they could run on the rails. The result is about as close as you’ll get to becoming a train driver.
The adapted buggies trundle along the tracks in convoy. Everyone gets to drive their own and speeds are limited to 20kph. This is only partly about safety, because it’s also the perfect speed for taking in the surrounding countryside.
This starts off sedate, but gets increasingly dramatic as the line cuts gorges through increasingly lofty hills and the farmland morphs into thick native forest.
With the sun beating down and birdsong the only noise apart from the buggy gliding along the rails, it very quickly becomes a blissful journey into the middle of nowhere.
The overnight stop is in Whangamomona, which has styled itself as an independent republic since a shift in regional council boundaries in 1989. Given the choice of the village’s rugby players having to play for the hated local rivals or seceding, independence was the only viable option. For many years, a goat was elected as president – and displays on the walls of the Whangamomona Hotel feature loving tributes to the now-deceased Billy.
The closer you get to the centre of the North Island, the more obvious the geographic forces shaping it become. Volcanic peaks soar upwards, fumaroles vent steam and hot-water springs burst out of the earth.
Lake Taupo – the great lake almost smack bang in the centre – is perhaps the most immediately obvious manifestation. But there’s plenty going on beneath the surface.
As our kayaks battle the unexpectedly choppy waves across it, our guide asks: “You do realise what you’re paddling on here, don’t you?”
The lake, approximately the size of Singapore, is one giant volcanic crater. When it last erupted in 186AD, it sent 100 cubic kilometres of debris across the North Island and the blood-red skies it triggered could be seen from China. At the time, New Zealand was uninhabited, but if Taupo goes again at a similar ferocity, it’ll be more devastating than any eruption in human memory.
For now, though, it’s more beauty than beast – an idyllic place for pleasure craft and paddlers.
Our target is a rather unusual set of artworks, to which there is no road access. In the late 1970s, Maori master carver Matahi Whakataka-Brightwell dedicated himself to transforming the rocks at Mine Bay. He started with small things, turning smaller boulders into lizards and fish, before painstakingly chipping and scratching the cliff face into an image of legendary Maori navigator Ngatoroirangi. It’s a startlingly comprehensive masterwork, made even more surreal by viewing it from a bobbing kayak rather than in a gallery.
While an eruption of Lake Taupo is not likely to happen in the near future, the volcanoes closer to the south need a sharp eye kept on them. Ruapehu, which hosts two major ski fields, last went off in 2007 and has exhibited plenty of warning signs since. Meanwhile, Tongariro’s Te Mari Craters went berserk in 2012, temporarily closing off part of what is regularly regarded as one of the world’s best day walks.
The 19.4km trek along the Tongariro Alpine Crossing passes almost entirely through terrain that belongs on another planet. The opening, gently uphill stretches are surrounded by lava fields and trickling streams that take on a rusty orange colour.
When it stops being gentle, however, the crossing becomes staggeringly domineering. The South Crater, for example, is a place in which to feel extraordinarily small. A dusty track leads across the middle of a vast grey circle, the ridges of Tongariro rising up all around like a gargantuan amphitheatre. To the west is the 2,291- metre-tall Ngauruhoe, technically one of Tongariro’s vents, but shooting up in a near-perfect cone as if transplanted from a children’s picture book.
If it looks familiar, that's because Ngauruhoe doubles as Mount Doom in the Lord of the Rings movies. And it doesn't need any Hollywood magic to make it look thoroughly intimidating. The hardy souls attempting to climb it have to contend with rocks tumbling down the gruesomely steep slope every time they try to get a footing.
The climb out of the South Crater goes along a ridge and looks down into the desolate, blackened Oturere Valley. Again, it’s Tolkien territory – this was Mordor in the films – and there’s an undeniable power in the sheer, uncompromising starkness.
The sense of being exceptionally privileged wells up as the ridge opens up more and more expansive views. Craters are stained red by oxides, vents pump out steam and small lakes take on dangerously dazzling colours.
The bright emerald waters have a siren-like lure to them, even though the toxic mess inside them would do the skin no favours. And from on high, it’s possible to get a full appreciation of Lake Taupo’s size and potential for destruction.
Standing on top of one volcano staring down into another would seem eerily weird anywhere else. But New Zealand does magically bizarre so well that such scenes start to become a joyous normality.
