It's minus 51C/60F. I’m in a 10ft by 10ft room with no windows. It’s snowing. I’m wearing my swimming trunks. And I’m very, very, very cold.

It’s the feet that are getting it worst. They are freezing, as I’m standing in about two inches of snow. The rest of me has just been warmed up in a series of saunas, steam rooms and whirlpools — which appear to have created a protective layer of warmth.

Then the cold really hits — all over. It takes about 40 seconds. And I have to leap out of the “Snow Paradise” room — which has a little sign by the door promising “a beneficial effect of total blood circulation and a congestion of the epidermis by reducing pulse frequency. Recommended time: two minutes.” You must be kidding.

Welcome to AquaCity, a giant geothermal resort in Poprad, Slovakia, which is now connected to the UK thanks to cheap new SkyEurope flights from Stansted. It has big, very chilly, plans.

At the moment AquaCity consists of a 50-room hotel set by a source of geothermal water near the centre of Poprad (population 56,000) between the High and Low Tatras mountains in eastern Slovakia.

There’s an Olympic-size pool, a heated outdoor pool (some parts warmed to 36C/97F), water slides, a solarium, and all the steam rooms, saunas, hot-tubs and massages you could possibly want.

The “Snow Paradise” room is just the tip of the iceberg when it comes to its colder treatments. In May, when AquaCity is doubling its number of rooms, it will also open a Cryochamber — with temperatures as low as minus 80C (minus 112F) — based on the principles of cryotherapy developed in Eastern Europe to treat athletes with injuries.

The treatment is said to be good for osteoporosis, rheumatism, back pain and cellulite — working by encouraging your body’s molecules to move to generate heat, thus creating “internal warmth”.

But I prefer more traditional methods of warmth-gathering. I try the Hellisch Steam room — which is simply a very good steam room with well- designed tile seating. Then I try Lucifer’s Sauna — a very nice sauna — and the Herb Inhalation Caldarium, allowing me to “feel how the power of nature” can affect my body. The heated outdoor pool is fantastic; even in December it is perfectly warm.

Next winter, a further 200 rooms will be added to the resort (my room was comfortable, warm, and nicely designed, but nothing special). There are also plans to build a mini Eden Project-style tropical garden: the Eden Project designers have already been consulted.

Jan Telensky, the Czech entrepreneur behind AquaCity, came across the geothermal source when meeting his in-laws during a visit to Poprad – which has a pretty 16th-century square with a church, but also lots of Soviet-era apartments. The source had previously been ignored as local authorities had hoped that their drilling would discover gas.

“I’m thinking of having discos at night and fashion shows,” Telensky said, “but it will all be 99 per cent energy self-sufficient, using geothermal heat. I want this to be the biggest geothermal resort in the world.”

Just stick to the warm bits — that’s my advice.

In brief

USP A giant geothermal resort between the High and Low Tatras mountains in eastern Slovakia that offers subzero treatments for the brave.

AMBIENCE Nascent Eden Project meets Soviet-era apartments. There’s an Olympic-size pool, a heated outdoor pool (some parts warmed to 36C/97F), water slides, a solarium, and all the steam rooms, saunas, hot-tubs and massages you could possibly want.

EXPERIENCE Spa treats range from Lucifer’s Sauna to Snow Paradise. The latter promises “total blood circulation” but freezes my feet after 40 seconds. A new Cryochamber will have temperatures as low as minus 80C (minus 112F) – cryotherapy is said to help osteoporosis, rheumatism, back pain and cellulite. It works by encouraging your body’s molecules to move to generate heat, thus creating “internal warmth”.

FOOD A spectacular sugar-cubed restaurant annexe to the spa will be ready for the summer season. Word on the street is it’ll be the best and healthiest restaurant in town. In the meantime, fill up on hearty but often greasy food locally for under a tenner a meal.

IN CROWD Wealthy Bratislavs and Poles and Czechs descending for the weekend; a handful of forward-thinking Brits are starting to invest.

WALLET WATCH Doubles start from £87 including use of all facilities; massages are extra and start from £15 for 30 minutes. SkyEurope (www.skyeurope.com) has flights from Stansted to Poprad from £54.

NEED TO KNOW AquaCity, Poprad, Slovakia (01582 748840; www.aquacity.sk)

Continued on page 2: more bizarre spas

More bizarre spas

Germany — chocolate massage. You’re covered in chocolate, then massaged with almond oil; £30 for 45 minutes. Best Western Bad Lippspringe (00 49 5252 9630, www.bestwestern.com).

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