The titiwai, glow-worms, as seen on the Black Abyss tour from The Legendary Black Water Rafting Co, lighting up a section of Ruakuri, one of hundreds of caves in Waitomo. Photo / Supplied
Deep underground in the caves of Waitomo, we float gently along a stream - pitch black but for a trail of titiwai, or glow-worms, twinkling above us.
Modern science tells us these little insects glow to attract prey, but I prefer one of the Māori legends, which says they are the scales left behind by a taniwha.
Less than three hours ago I woke up in my Auckland flat, and now here I am 60m below ground, marvelling at glow-worms, of all things.
The fact we have these in our "backyard" is what makes Aotearoa so ridiculously amazing, and what we love to brag about to overseas friends.
But I had never been here.
So one long weekend a friend and I were off to do just that, along with ticking off a couple of other bucket-list adventures in nearby Rotorua - but we'll get to that.
After just under two hours' drive, we arrived in the small southern Waikato settlement of Waitomo.
We were booked in with one of the pioneering caving companies, The Legendary Black Water Rafting Co, on their Black Abyss tour, dubbed an "experiential roller coaster".
After a quick - but thorough - induction, we started abseiling from restored native forest above ground to some 30m below, deep into Ruakuri cave, named after a young Māori hunter who was attacked at the cave entrance by a pack of dogs about 500 years ago ("rua" meaning den and "kuri" dogs).
If that was not adrenalin-inducing enough, a pitch-black zip line followed, before we plunged into a frigid stream.
But this was where things began to slow down, the scenic part of the "roller coaster" taking over, as we gently floated through this wondrous titiwai-lined cathedral, in tyre-tubes.
As we paused and our eyes adjusted to the darkness, Joel, one of our two guides, described the cave origins, how 30 million years ago this mound of calcified limestone - made up of dead sea creatures - was thrust up from the seafloor by the grinding Australian and Pacific tectonic plates.
Rain gradually eroded tiny cracks into a vast expanse of more than 300 known caves.
Māori dubbed the area Waitomo, in short, "wai" for water and "tomo" as entrance or hole, with deeper significance given to their creation story, and as a path to the underworld.
BWR works closely with the Ruapuha Uekaha Hapū Trust - which the company leases the land off, following a 1989 Treaty of Waitangi settlement – to ensure their practices are in line with tikanga, protocol, and that the correct stories of the caves are told.
Not only did this history broaden the experience, but it added a mystical layer, with images of taniwha slithering through the cave.
The tour was definitely not for the faint-hearted.
But both our guides were incredibly experienced and knowledgeable - "T'VE" (he wouldn't tell us his real name) had more than 30 years' worth - and their calming presence made it all the more enjoyable.
Plus they were particularly skilled at long exposure photography, with plenty of opportunities for photo shoots.
Back at the Waitomo Homestead cafe, operations manager Logan Doull told us how the caves were the company's lifeline – and for many in the small town – and as such conservation has been a major part of the operation since it started in 1987.
Their environmental team measures everything from wind speed and direction, and carbon dioxide levels constantly - too many people inside breathing carbon dioxide can erode the calcium stalactites in the caves.
They also work with farmers and landowners in the surrounding catchment on riparian planting to reduce sediment and improve water quality.
"We are always working to ensure what we do is having as low an impact as possible," Doull said.
Next up we were off to Rotorua, about a two-hour drive away through rolling central North Island hill country.
Activities are aplenty in this tourism hub, but Rotorua Canopy Tours offers one of the more unique zip-line experiences in the world.
The award-winning Original Canopy Tour, set up in 2012, combines adrenalin and environmental education. It's situated in an ancient tract of native forest in the 500ha Dansey Road Scenic Reserve – one of the few areas untouched by historical loggers.
The three-hour journey takes you deep into the forest, before shooting along cables while hanging from a harness between platforms perched in 1000-year-old rimu - some towering 60m high.
There were definitely some nerves at times, particularly while waiting for those ahead to have their turn, but as soon you stepped off the platform it was time to soak in the view.
It's a unique perspective above the canopy, and one normally only afforded to birdlife, which our guides played to, and encouraged us all to embrace our inner tūī, which also helped take our minds off the drop below.
In 2017, the company added the Ultimate Tour to its range, which is a slightly more adrenalin-oriented adventure, with more zip lines, higher, and longer – including a tandem one running a massive 400m.
Conservation is a major part of the overall operation, with portions of the tour fee going towards the Canopy Conservation Trust, which supports trapping and pest control efforts in the reserve.
Our guides told us how their efforts had seen a massive turnaround in ecology, with now countless rare species of native birds, invertebrates, reptiles and fungi making the area home.
Even for someone who has grown up hiking all over New Zealand, this patch of forest was something very special.
The tour also provided a rare opportunity to feed wild North Island robin/toutouwai and tomtit/miromiro, which seem to have adapted to the custom and hovered around our group throughout.
After a quick bite to eat for lunch we were off to sample another activity Rotorua is gaining quite the reputation for – mountain-biking.
Given it'd been a few years since my friend and I had been on the saddles, we were quite excited to try out some e-bikes with Electric Bike Rotorua.
"Flattening the hills", is how sales and operations manager Joe Lindsay described the increasingly popular technology.
He and his partner, Frankie Kebbell, set up the company in 2015, and have seen massive growth in popularity for these modern machines ever since.
They offer a range of bikes for hire, from cruisers for checking out the flats, to full-suspension, top-of-the-line mountain bikes, with huge batteries that'll assist you up to speed of 30km/h - uphill even. We knew what we wanted.
Our destination for the afternoon was the Whakarewarewa Red Woods Mountain Bike Park, which is about a 10-minute ride from the city centre.
It is one of the best-established mountain bike parks in the country, and with about 130km of continually evolving trails, there is something to cater for all levels, from beginners and family groups through to experts looking for extreme action.
But if, like us, you're only riding for a day, it'd be incredibly easy to get lost, or end up going down one of the more "extreme" tracks.
So that afternoon Joe took us on a private guided tour.
We set off from town, quickly skirting around the lake via some geothermal hotspots.
For a few minutes, it felt like we were riding on another planet, with steam billowing across the landscape and mud bubbling alongside us.
Soon we were at Whakarewarewa, home of the picture-perfect 100-year-old redwood trees.
We made our way uphill and deep into the forest, with normal mountain bikers glaring as we zipped past them, without even a heavy breath between us.
Joe quickly garnered our skill level - i.e. not a lot – and tailored the ride to it, expertly selecting suitable tracks and pushing us just enough to get the adrenalin pumping.
Soon enough he had us whipping around corners, rolling off ledges - small ones - and even trying out the odd jump.
We soon found our "level", after a light tumble, but that's what it's all about.
The best part of mountain-biking, we quickly discovered, is going downhill. It's fast, and you don't have to pedal.
But with the little electric motors, the uphill parts didn't matter in the slightest - quick flick to "boost mode" and the job was done.
We ended up covering probably two to three times the area we could have on normal bikes.
The last track, known as Eagle vs Shark, was by far our favourite, and I think Joe knew it would be.
Fast and flowing, we were absolutely buzzing once at the bottom.
It had been a huge two days of adventurous activity, and all we felt like was a soak in the hot pools, which after all, is usually why people end up in Rotorua.
As we made our way back to Auckland after just three days away, we couldn't believe we hadn't made the trip before, and couldn't wait to tell all of our friends stuck overseas what they were missing.
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