"Gripping their harness tightly, I try with all my might to stop the eager pack of husky dogs from tearing loose. But not even a fleet of armoured tanks could halt these powerful animals and dampen their desire to run.
Blue eyes glinting wildly in the violet wintery half-light, lead dog Simbad burrows his paws into the thick snow as if revving up an engine.
Barking, wailing and howling impatiently, eight packs of dogs are raring to take their, understandably nervous, passengers on a ride through remote Arctic valleys visited only by a fortunate few.
But as the noise reaches a deafening crescendo and my fingers turn blue from both cold and constricted blood flow, the starting signal is given, blissful silence falls and the magic of this wild and other-worldly landscape takes hold.
Lying just 819 miles from the North Pole, Longyearbyen - the capital of Spitsbergen which is part of Norwegian archipelago Svalbard - is one of the northernmost settlements in the world.
The former mining town already attracts tourists during the summer season, many hoping to catch a glimpse of the fierce but irresistibly enigmatic polar bear. But now visitors are coming specifically for the winter months, to experience adventurous activities such as dog sledding, ice caving and snowmobile rides through the Arctic Desert. Thanks to the warmer influence of the Gulf Stream, the climate is "mild" enough to make visits possible throughout the coldest periods - even though there were reports of a wind chill factor of minus 50C just days before our early March visit.
Thankfully, it's only minus 20C during our dog sledding adventure with the Green Dog yard in Bolterdalen, ten minutes outside Longyearbyen.
As night falls, along with the temperature, owners Claire and Martin invite us into their traditional trapper's hut to warm up in front of a crackling fire with a traditional Arctic meal.
Looking up at the sky, I watch satellites whizz past overhead.
I'm told it's possible to count up to 14 in orbit, and for the duration of my stay I'll have the fastest internet connection I've ever experienced.
Inside the cosy hut a muskox hide hangs from one wall, while the jaw bone of a polar bear is less a hunting trophy and more a reminder of the harsh and hostile environment we're in.
As minke whale and reindeer are cooked on hot slates at our table, local guide Anneka explains why she turned her back on her homeland, Australia, to come and live here.
There are 41 different nationalities residing in Longyearbyen, quite impressive for a town with a population of just 2,000. Many are attracted by high salaries in the mining industry and the archipelago's duty-free status. But others have simply been seduced by Svalbard's exotic beauty; being one of the few places where nature still holds the reins.
"For me it's the extremes of light," says Anneka, who's been here for more than five years.
"The polar nights are some of my favourites, and we know there are always longer days to look forward to."
It's the advent of these longer days that we've come here to celebrate.
Our visit coincides with Longyearbyen's return of the sun festival, which takes place on March 8 every year. But when we arrive, I'm surprised to find the town already bathed in hazy orange light. The sun has been hovering above the horizon since mid-February, clawing back half an hour of daylight every week.
I'm told the festival commemorates the moment when rays finally stretch above the mountains and strike the old hospital stairs, one of the town's few historical monuments (the hospital building has long since disappeared), now protected under a local law that prevents tampering with any building or item pre-dating 1946.
Walking past semi-frozen fjords, where pancake ice floats in the viscous water and wisps of swirling vapour rise into the air, we climb the slippery path to the stairs. Groups of young children in thermal suits and ski goggles wear collars shaped like sun rays, some carrying bright solar-themed banners.
But despite singsongs, a TV crew and a speech from the mayor, the sun fails to turn up to the party at 12.18 - as it has done, with only a couple of exceptions, for the past 15 years.
Wolfing down doughnuts and waffles afterwards inside Svalbard Cathedral - the world's northernmost church which was built in the Fifties and serves as the town's main community hub - no one seems particularly perturbed.
The festival is just one of many peculiarities which make Longyearbyen such a fascinating destination: the town has it's own colour consultant, responsible for selecting the nature-inspired shades of houses; the absence of any social security provision means the average age of residents is just 37; and the number of snowmobiles far exceeds residents.
With only 46km of road, cars are practically useless here, and the best way to explore the wilderness is on skis.
Spitsbergen Travel organise snowmobile safaris through the Arctic Desert, a vast, dry, icy expanse that forms the second largest desert in the world (after Antarctica), and receives about the same amount of precipitation as the Sahara.
Clinging tightly to my driver as we zig-zag through narrow valleys, shifting weight from side to side to balance the heavy vehicle, I experience a mixture of panic and exhilaration.
Leaving snowmobile trails behind us we plough through pristine snow, taking paths that appear totally untouched. As ice flakes gather on my eyelashes, I squeeze my cheeks to avoid frostbite from the blistering wind.
Polar bears have been known to roam here, but at this time of year most tend to stay in the eastern part of the archipelago.
A scattering of Svalbard reindeer on the horizon are the only forms of life. Specially adapted to these difficult conditions, they even cease to urinate during winter months in order to conserve energy. In this beautiful but harsh environment it's a wonder anything can survive.
Some 60% of Svalbard is glacial and, during winter months, its possible to go caving into ice chambers below Longyear glacier.
While wondering if warmth will ever return to my toes, I'm bundled into the back of a snowcat, a windowless sardine tin on caterpillar treads, which hulks and bumps up the side of a mountain.
Every year, scientists bore a tunnel into this 200-year-old glacier, which I'm reassured is stable (Glaciers in the southern hemisphere can move five to six metres per day).
Kitted out with crampons and a hard hat, I enter an igloo to find the cave entrance - a gap the size of a manhole that descends into darkness.
Using a rope I lower myself into the frozen chamber, where rocks and debris from the mountain appear encased in clear glass cabinets.
In places the ice has formed tubular bells, which chime different notes as I brush past. Armed with drum sticks, one band even came to play music down here, our guide, Annamarta, proudly informs us. Although I can't imagine where they managed to fit an audience.
Scientists also discovered a flower in this natural deep freeze that's never been seen before in Svalbard, Annamarta goes on to say.
The fact something so delicate could be preserved in such as hostile place is astounding.
But, as I'm quickly learning, Svalbard is a place that seems to thrive on such extremes."
Travel facts - Svalbard
Sarah Marshall was a guest of Hurtigruten (0203 5826 642; www.hurtigruten.co.uk) who offer two, three and four-night land-based
short breaks in Spitsbergen in March, May, October and December. A two-night stay in March starts from £811pp, including accommodation and excursions (a 45km snowmobile safari through the Arctic Desert, ice caving and a wilderness evening). Flights are extra but can be booked