Last time Deception Island’s volcano erupted was in 1970, so there isn’t any immediate danger of getting blasted out of the crater still wearing a bikini.
The water temperature is more worrying: -1.9C, with chunks of ice bobbing around between the penguins.
It doesn’t look inviting, especially with snow covering the perimeter and an icy mist rising from the surf.
There’s a small margin of black sand, though, to strip down from three layers of thermals, gloves and waterproof trousers to just a swimsuit.
Join the Weddell seals for a swim (Picture: Jen Mills)
Why are we doing this? (Picture: Jen Mills)Welcome to the polar plunge: a rite of passage for anyone visiting Antarctica brave or idiotic enough to jump in.
There are quite a lot of us fitting that description, ranging from elderly women in tank tops to a tattooed man who grimly waded in until waist height, then started doing butterfly stroke.
We’re trying to achieve the bucket list item of a dip in the Southern Ocean. This seemed like a good idea from the comfort of MS Midnatsol’s bar, but once our toes touch the frozen sand, it suddenly… doesn’t.
Nowhere on the White Continent qualifies as a spa – and if that’s what you’re looking for, then you need to go somewhere else.
If you want the power of earth’s last wilderness, though, then you may as well go all the way and put your head under.
Deception Island is a popular place for the plunge. Part of the submerged crater wall collapsed in a 10,000-year-old explosion, creating a horse shoe bay called Port Foster which acts as a natural harbour.
Although there’s thermic activity going on (the continent’s only other active volcano is Mount Erebus), put aside thoughts of the Blue Lagoon.
The surf right at the edge of the caldera is so hot you can see bubbles boiling up, giving off a sulphuric smell and sending clouds of steam across the ice.
That gives a false impression, because once you wade in it’s well below freezing.
The view from the beach (Picture: Jen Mills)I’d jumped off an ice floe in the Arctic in Greenland a few months earlier – which I assure you is not how I usually spend my weekends – but this is a different level of pain.
I dash in (only sprinting will do; there’s no possibility of easing yourself in toe by toe) and feel immediate pain. The water is like needles, each hurting at first then bringing a creeping numbness, like the anaesthetic effect of holding an ice cube against your skin.
It’s such a bodily experience of cold I can barely fight my way in further, against every instinct saying ‘turn around and grab the nearest waterproof jacket’.
This was meant to be my Lewis Pugh moment, but I barely make it up to my neck. After achieving the minimum depth necessary to claim I had ‘swum’ in the Antarctic, I sprint out like a gentoo penguin being chased by a killer whale.
Mist rising from the beach (Picture: Jen Mills)By the time I reach the shore, my toes have so little feeling I could have been walking on blocks of wood, and it’s hard controlling my fingers to pull my clothes back on (over the swimsuit, as taking more clothes off is inconceivable).
All that’s in my head is that I now know what the start of frostbite feels like. I hope it’s reversible.
My plunge partner had scared me beforehand with tales of leopard seals dragging swimmers to the bottom of the sea, recounting the story of a snorkeler drowned in 2003.
The submerged crater of an active volcano (Picture: Jen Mills)‘They are worse than hippos. They’re terrifying,’ she told me before we went in. ‘I don’t know if I’ll do it. They could take you down 200 metres and no one would ever find you.’
It seemed a tall tale over Irish coffee in the ship’s lounge, but Google proved it 100% legitimate. Kirsty Brown died aged 28 while working as a scientist near Rother Research Station. Colleagues from the British Antarctic Survey colleagues managed to pull her into their boat, but she couldn’t be resuscitated.
Thankfully we’re in the shallow end of polar swimming, so the deepest any seal could drag us was four feet.
It’s an unforgiving landscape (Picture: Jen Mills)The real danger is the temperature. Cold water swimming is famed for its apparent health benefits, but it can also be fatal.
The shock can bring on a heart attack, so the ship’s doctor is on hand in case of any problems, wrapped in a cocoon of waterproofs labelled ‘Medical Team’.
He warns us not to leap into a hot shower immediately, because the change in temperatures could be dangerous. Instead, he says it would be better to start with lukewarm water and gradually increase the temperature as our bodies adjust.
Do it with a doctor on hand (Picture: Jen Mills)I survive my 60 second immersion but have to lie down afterwards with an intense headache, feeling exhausted and sick.
It’s a reminder that we are in a wild and dangerous place, thousands of miles away from the nearest hospital.
In the cosiness of our cabin, it’s possible to forget that – but in the freezing ocean, it’s clear.
You’ll gain a new respect for the Weddell seals and penguins spectating from the beach, while struggling to manage even 60 seconds in their habitat.
Used as a base for hunting from 1819, this is one of the few places in Antarctica where you’ll see obvious evidence of human activity.
Abandoned whaling buildings (Picture: Jen Mills)
Nathaniel Palmer is believed to have been the first to explore the island, which is one of the South Shetlands. In four years, he and other American and British sealers hunted around 500,000 seals.
It was later used by whalers in the early 1900s, and old industrial buildings remain on the shore, along with the shells of their wooden boats. You can’t touch them as they’re fragile historic artefacts, but they make for eerie photographs.
If your ship drops anchor in Whaler’s Bay, you’ll have the chance to hike up to Neptune’s Window.
Looking through this narrow opening between pillars of rock, Nathaniel Palmer is said to be the first person to look at the continent of Antarctica
How do you get here?
I travelled with Hurtigruten on a 13-day expedition cruise to the Antarctic Peninsula and back. Our first stop was Deception Island, and we then went on to Half Moon Island, Cuverville Island, Orne Harbour, Neko Harbour and Wilhelmina Bay – as well as making a landing on the sea ice.
MS Midnatsol docked in Whaler’s Bay (Picture: Jen Mills)
As the weather can be so unpredictable, there’s no guaranteed itinerary, with ice conditions dictating the route. Deception Island tends to be a reliable stop, given its natural protection from the elements.
Tour operators bring guests to Antarctica during the Austral summer, with most ships departing from Ushuaia in southern Argentina and sailing across the notoriously rough Drake Passage.
You’ll need to make your own way to Buenos Aires (British Airways and Norwegian offer direct flights from London in the region of £500 to £700 return) and Hurtigruten arranges a charter flight to Ushuaia from there.
Prices for ‘Antarctica: Highlights of the Frozen Continent’ start at £5,880 per person.
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