Nose pressed to the van window, I strain for a glimpse of the wilderness through the pitch black. Our guide, Tom, is at the wheel, navigating the unforgiving terrain of the Fljót Valley, a mountainous fold of Iceland's Troll Peninsula. We're en route to the remote Deplar Farm for a weekend designed to reboot our wellness through adventure.
As we travel, Tom regales us with tales of Icelandic life. Between stories of sacred elf hills, trolls and discovering the value of a box of Yorkshire tea to a desperate neighbour willing to trade for a taste of home (four winter tyres), we learn that the best way to tackle the days ahead is by becoming true Icelanders. "Þetta reddast," Tom says, which roughly translates as "it will all work out". Combining demanding outdoor activities with Viking-inspired wellness treatments, Deplar Farm is going to push us to our limits.
Surrounded by 2m of thickly packed snow, the lodge comes into sight. Housed in a former sheep farm, it's snugly clad in black timber and capped with a verdant living roof. We're welcomed by the team - staff outnumber guests at Deplar - and ushered in, out of the cold.
At dinner, just as I'm tucking into forkfuls of lightly seared Arctic char, we're beckoned outside. "You must have brought something lucky with you," I'm told, as the ghostly northern lights undulate across the sky. The lack of light pollution at Deplar makes it one of the best places for catching the phenomenon. Wrapped in soft woollen blankets, hot chocolates in hand, we take in the show, before frostbitten cheeks send us back inside.
My bedroom - one of 13 - is named Flóki, after the first Norseman to intentionally sail to Iceland. I can't help feeling it's apt, as I bed down, anticipating tomorrow's adventures.
I preempt my alarm's 7am call to watch the first kiss of pink-tinged daylight touch the valley. At this hour, the landscape sits eerily silent, blanketed in a layer of untouched snow.
Taking my seat at the communal breakfast table, I order a platter of salmon, homemade granola with skyr (an Icelandic yoghurt) and hot-from-the-oven rolls. As the golden light of late dawn cloaks the dining room, other guests appear.
Jack and Audrey, an American couple in their 60s, are part of the Deplar Farm family, with guides greeting them by name. "This is the third day of our third trip here," Jack tells me. "We always look forward to it. We're thinking of adding heli-skiing next year." (The lodge has two heli-pads to facilitate the adventurous ski style.)
I ask if they have any tips for a Deplar first-timer. "Always say yes, and do all the things you'd normally say no to," says Jack. "You're with some of the best guides in the world, so there's nowhere safer to try something that scares you."
At breakfast, my group meets our appointed guide. Originally from Poland, adventure specialist Karolina comes with an extensive list of qualifications - avalanche training among them. We head out to "The Shed", which houses Deplar's equipment. It's packed with maps, rescue gear and, unexpectedly, a drum kit.
Having checked the morning reports, Karolina explains that weather conditions are on the turn and that fat biking - our original plan - is out. Instead, we'll be snowshoeing.
After clipping our snowshoes into place and adjusting our walking sticks, we set off in the sunshine. The crunch of fresh snow, crispness of the air and the ease with which I find myself walking gives me confidence, but that's ripped from under my boots as the wind picks up and we find ourselves trekking through a snowstorm. Between missteps, frigid lungfuls of air and snow-obscured vision, my certainty turns to fear. Pushing on through the harsh terrain, I don't have time to panic. Before I know it, I see the welcoming sight of the lodge ahead.
Activities at Deplar come in pairs: one adventure; one wellness. Often, it's hard to tell them apart.
The sauna is built into the earth, sheep grazing above. It's grounded in the landscape and folklore of the peninsula. After snowshoeing, the idea of a relaxing steam is enticing, but, in true Deplar fashion, this is no normal spa experience. The Viking sauna - a ritualised coldwater therapy - is not for the faint of heart.
In the sauna, enveloped by the soothing sound of Norse chants, Karolina, a certified breathwork practitioner, guides us in setting intentions, working through our breathing and acclimatising to the extreme heat. It's comforting, until she utters the five words: "Who wants to go first?"
I'm unable to make eye contact as she patiently waits for a volunteer. But, while not brave enough to raise my hand first, I jump at the chance to go second.
The first gust of wind and feeling of ice beneath my feet leave me gasping. Karolina gently instructs me to hold onto the bitterly cold rail of the plunge pool as I lower myself down the steps. The shock is intense. It becomes a fight of mind over matter as I will myself to breathe slowly. Karolina reminds me to keep looking into her eyes and to fight the urge to breathe in short, quick gasps.
It works. I'm up to my neck in freezing waters, taking deep, even breaths. I last a few more seconds, before stepping out. The walk back to the sauna is calm, almost easy compared to the plunge. I feel invigorated.
The trial of opposites is a theme over the following days. Striking out towards the coast, we meet the Icelandic horses at Langhús Farm, headed up by husband-and-wife-team Laki and Lukka.
"They're steady and obedient, and they're our family. It's in their nature to be friendly, just like us," Laki grins, as he adjusts a stirrup on my companion. Falcon, a cream-toned, 16-year-old male, is cool and collected, and quite used to setting off for the snow-covered hills.
Our ride is spent battling strong winds, but when we return to Deplar, there's a soothing end to the day: gong bathing. Designed to reduce stress and aid sleep, the practice uses the vibrational sequences of Tibetan singing bowls and guided mindful relaxation to induce a meditative state.
Two-thirds of the way into our session, lulled by the dulcet instructions, I am convinced - and glad of there being no snow involved.
Later, we take a dip in the geothermal pool, sipping amaretto-spiked hot chocolates, noses frosty, as the snowfall continues.
My final morning brings with it one last adventure - news of an incoming snowstorm. Predicted to hit in the early afternoon, the cold winds are forecast to bring enough snow and hazardous conditions to block all routes out of the valley.
With real-world responsibilities calling, we reluctantly agree on leaving early rather than extending our stay for the extra two days needed for the storm to clear. Transport and flights rearranged, Karolina informs us that we still have time to fit in one final escapade: snowmobiling.
"How fast can we go?" I ask in glee, as we snap on our goggles. Our guide laughs: "As fast as you like."
Armed with our destination, a spot on the horizon identified as "The Lakehouse", and a basic understanding of ensuring the smooth operation of the 225kg machine, I set off. The roar of engines is all I hear as I race over the frozen lake, pushing the snowmobile, and myself, to the limit.
On arrival, we pull on our swimsuits once more and brave the snow underfoot to reach an outdoor tub, where we let the warm waters envelop us. Then, this being Deplar, there's one final challenge: sprinting barefoot through the glacial temperatures back to the cabin.
It's with a deep breath, and a newly developed taste for adventure, that I take the first step.
The Eleven Life at Deplar Farm package costs from £2,350 a night (based on two sharing).