Warm up in the depths of Iceland

As I was sitting in a hot tub in downtown Reykjavik, a paunchy man with a Viking-like thatch of red hair struck up a conversation: 'Do you know you are sitting in water that is 1,000 years old?'

I smiled politely. A hot tub history lesson - please!

'This is rain water from when the first people arrived in Iceland,' he persisted, leaning closer. I shifted along the ledge. Perhaps it was time for tub two, a thigh-smarting 40C. Here sat three businessmen in trendy spectacles, jabbering in Icelandic. We were joined by a trio of nubile 14-year-olds in bikinis, lithe and tanned after four months of round-the-clock sunshine. Aha, I thought. Now let's see what happens.

But nobody batted an eyelid. It was as if we were all wearing mackintoshes and waiting for the bus. Didn't these people get it? Hot tubs are sexy! Everyone in suburban Britain knows they go hand-in-hand with decadence and extra-marital affairs.

But not, evidently, in Iceland. 'You British go to the pub,' Skuli, a taxi driver, explained as we simmered in tub three (a whimper-inducing 42C). 'The Americans go to their coffee shops. Icelanders go to the swimming pool. It's where we do our socialising.'

In such a bleak climate it makes sense. An Icelandic winter throws every element at you, needling you with rain, peppering you with hail and snow, shoving you sideways with gusts of wind. Every five minutes the skies give way to rainbows and glittering sunshine, but to get truly warm, you have to wallow in geothermal waters.

Reykjavik, Iceland's groovy but diminutive capital, has seven public baths fed by different hot springs and each is said to carry different benefits: one helps arthritis, another asthma, another is good for your skin. All are good for stress, according to a recent study. It's the hot-cold-hot that does it.

Entrance is £1.50 for a cluster of outdoor hot tubs, a steam sauna and a large, outdoor thermal swimming pool at 29C. Some have extras such as masseurs, but the ritual for bathers is always the same: simmer, steam, swim. There is no stench of chlorine, no cracked tiles or dank, concrete corners. The buildings are bright, warm (thanks to geothermal central heating, which serves all the city's housing) and stylish.

All this makes for a surprising revelation: Reykjavik is great for a winter spa holiday - and a super cheap one at that.

Each day I circled a different pool on my map and built it in to a lazy programme of cosy coffee houses, small designer shops and modern galleries. In the morning I would share a tub with workers and, allegedly, a politician or two. But I preferred the evening, when the sky darkened with scudding clouds and the elements closed in. To soak in steamy water in such conditions seemed, to me, fabulously decadent. It was also wonderfully relaxing - until I caught sight of myself in a mirror. Beetroot, with a remarkable nuclear glow. Why hadn't anybody else gone this colour?

So if thermal wallowing is the norm, what counts as pampering in Iceland? I was tipped off by Sigmar, a television presenter and hot tub encounter. 'Go to Mecca Spa. You'll emerge a beautiful woman.' Thanks, Sigmar.

I took a taxi to the eastern suburbs, past trendy apartment blocks, their huge windows facing snowy Mount Esja across the bay. Mecca Spa was a luxurious temple to wellbeing, much like any other spa-cum-beauty parlour. The difference lay in its ingredients. Hot geothermal water, black volcanic stones and herbs combined in a massage that left me, if not a beautiful woman, at least a limp and pliable one.

The original Viking leisure centre is the famous Blue Lagoon, half an hour from Reykjavik: a milky-white natural basin set in rough black rock, fed by a hot spring. Soft pumice polishes the soles underfoot and, if slapped on your back, makes an excellent exfoliant.

It is hard to imagine bloodthirsty Eric the Red buffing his skin there, but the place has a potent atmosphere. Strange shapes loom up in the billowing steam, especially at twilight. A businessman who waded in after me bobbed around wearing a plastic Viking hat. In the half-light and swirling vapour he looked eerily at home.

The water here was hot - almost too hot in parts, where unseen currents swirled. Victorian visitors would test Iceland's bubbling springs by cracking eggs into them. After a quarter of an hour I was beginning to feel slightly poached myself.

As the lagoon emptied and the skies blackened menacingly, I had a sudden panic that I would miss the last bus and be stranded in this weird landscape all night. And this was Saturday night, the capital's much vaunted big night out when everything stays open until 5am. My flight was early on Sunday - why bother going to bed?

Alas, hot tubs and clubs do not mix. Bleary-eyed at 5am, waiting for the airport bus after six hours' sleep, I was shamed by a trio of boys in trendy trainers bursting through the hotel doors. 'See you in the morning,' they cried, staggering to their rooms.

I might have failed at Icelandic decadence, but I left Reykjavik with clear skin, a supple body and that ruddy glow peculiar to all who live here - as if I'd been slapped about the face and sent out into the snow to play.