Everything speaks against undressing now and thinking of something as absurd as swimming here. In front of us: a crystal-clear glacial lake. Fresh snow lies on the shore; bone-chilling cold around us, and a not exactly inviting water temperature of 1.6 degrees. Body and head both say no. "Just don't think twice, take off your clothes and get into the water," says our guide, who wants to give us the ultimate cold kick this morning. Ice swimming is trendy - it's supposed to strengthen the immune system and be addictive once you get accustomed to it. The first steps into the icy water are a shock. The cold cuts off your breath, hammering your skin like pinpricks. "Breathe into your stomach calmly," says our instructor, who has years of experience with winter swimming: "Start slowly, and notice exactly how your body reacts." Ice swimming is an extreme sport - you should never do it alone. And you should definitely have a doctor check you out beforehand to make sure you're fit enough and that everything is okay with your cardiovascular system.

Alone in the lake

After a few puffs, the cold is no longer so bad, and a great feeling of freedom sets in. Ice floes drift past us on the water and create a spherical sound. "Be careful not to cut yourself on them," says our guide, who, like us, is beaming all over. The body emits huge amounts of adrenaline, euphoria sets in; pure happiness to be completely in the moment. It is unearthly beautiful how the sun glitters on the water. An absolutely exclusive bathing feeling, so alone in the lake. What actually drives us to leave our comfort zone? Not to relax like everyone else in the spa or to lie lazily on the beach? The answer is simple: It is only through challenges that we realize what we are capable of. We dare to do things we would never have imagined, the adrenaline rush is indescribable. Often, you don't have to switch off at all, but simply turn it up a notch to feel alive in every fiber of your body.

Ice swimming is becoming increasingly popular. ©GettyImages

Somewhere in nowhere 

Anyone who has ever dared to go heliskiing knows what we're talking about: usually the journey itself is already a great adventure, into the winter wonderland it sometimes even goes by snowmobile to a remote hut somewhere in the middle of nowhere - and then by helicopter to the mountains, where endless untouched slopes await. It's a queasy feeling the first time: What, I'm supposed to ski down these steep slopes? Won't I sink into the snow? "Self-confidence is important, as is mental strength. For many slopes, medium ability and a little practice in deep snow skiing are enough," says our guide. He has to disappoint us on only one thing: "Only James Bond jumps out of a helicopter." We land at the top of the mountain, and then we're off into the endless, untouched white. We have to imagine the appropriate soundtrack - driving with headphones is strictly forbidden: Guides must be heard at all times, not just in case an avalanche is approaching. Canada is a popular destination, but Iceland, Sweden, Georgia and Kamchatka (in Russia's Far East) are also good places for heliskiing. And let's not forget the Himalayas. The provider Eleven Experience takes heliskiing to a new level with the dream destination Chile. During the ultimate "Southern Hemisphere Ski Experience", as it is called in the brochure of Eleven Experience, you fly past imposing glaciers, experience the breathtaking Andes from above; there, where eternal winter reigns. Patagonia means endless expanse, which many associate primarily with summer and hiking. The luxurious "Rio Palena Lodge" is located in the middle of nowhere - true adventures begin in a remote area. The allure of the extreme leads to landscapes that take your breath away. The ultimate goal: in the midst of the gigantic mountain and snow worlds you feel tiny. Journeys like these are also expeditions into yourself: How do I deal with fear? How do I act when faced with new, overwhelming experiences? What is it like to expose myself to the elements? If you do extreme things on vacation, you'll go home satisfied - and perhaps take one or two experiences with you into your everyday life or job. Don't hesitate, just do it! You can do it!

Heliskiing brings the ultimate adrenaline rush and perfect powder experiences. ©GettyImages

Dog tired in igloo

On a husky tour of several days you'll also be close to the forces of nature. The powerful dogs, the icy wind in your face - after an hour at the latest, your eyelashes are frozen and you learn to love the cold, just like the dogs, who feel perfectly at home in sub-zero temperatures. But the great thing about husky tours is not only the snowy landscape (through which you glide amazingly fast with the sled), but above all the relationship you build with the animals - when you feed them, when you learn how a pack works. Wonderful, how in the evening animal and human proverbially dog-tired fall into a deep sleep, until it starts again the next morning. The simpler the hut or overnight accommodation is, the nicer it can be. We are anyway overfed with luxury and partly much too softly bedded. Since in the vacation less is often simply more: To spend the night in the winter in the tent or to snuggle into the warming sleeping bag has a special charm - and in the morning then to melt snow to brew a strong coffee. This is how you feel life with all your senses. Without wanting to be esoteric, survival training is not just an ego boost: somehow it's also reassuring that you can still survive largely on your own. At least with huskies on a leash that are in their element.

Endless expanses can be explored by dog sled. ©Emmanuel Berthier

Overwhelming starry sky

Moreover, the child in us awakens. Who didn't build an igloo in winter and dream of spending the night in it? Nowadays, there are numerous igloo providers, some of which require you to build the snow cave yourself. More comfortable, however, are hotels in the far north (where the temperature inside and outside can be a good 50 degrees!) that play with igloo aesthetics. The most famous is the "Kakslauttanen Arctic Resort" located in Lapland - the cozy glass igloos give a view of the sky, so with a little luck you can see fantastic northern lights. A night in the Pyrenees is no less spectacular. The term "firmament" takes on a whole new dimension there: you almost feel oppressed by the many stars, which shine so brightly that you can hardly close your eyes (even with excitement). In some nights up to 60 shooting stars per hour are to be seen - there one relatively fast the desires go out. It is better to make a list at home. On the mountain Pic du Midi, at an altitude of 2,877 meters, there is a fantastic old observatory, which is also a hotel. Only 27 people can be on the mountain at one time, a manageable group of adventurers. After dinner and a cocktail, the guests get ready for a long, exciting night. But no one has come here to go to sleep early, although the high-altitude air quickly makes you tired - after all, the highlight takes place in the dark: An expert explains the starry sky to the small group, describing the countless constellations. You can't help but be amazed. And the next morning, the gigantic telescopes in the observatory are visited. One thing unites all these quite different extreme experiences: They can be conveniently booked online. Never before has it been so easy - and not least so safe - to leave your comfort zone and go out into the adventures that you can usually only experience in freezing cold. You just have to give yourself a jolt. It's sure to pay off.

Good to Know

• Northern lights very close
  The best time to see the aurora borealis is between September and March. Around the equinoxes it is usually seen particularly intensively.

• Perfect powder
  In the Northern Hemisphere, the best time for heliskiing is from January to April, while in Chile and Patagonia, for example, you can find perfect conditions from July to October.

• Winter bathing
  Ice bathing is the latest trend - but before you jump headfirst into the ice-cold water, it's worth taking a workshop with experts to learn the (super)vital basics.

• Timely planning
  Many providers focus on quality instead of quantity and deliberately keep tour groups small. Therefore, it is worth planning the ultimate ice adventure in good time.

The top providers

• Patagonia Grand Class
  The ultimate heliskiing experience awaits: Guests stay on a luxurious yacht and are flown daily to the mountains by private helicopter. heliskiguides.com

• Wild Iceland
  From ATV tours to ice climbing - adventures for every taste await here. icelandluxurytours.com

• Luxury in the far north
  Four-day dog sledding tours with accommodations in elegant chalets and lodgings with sauna and jacuzzi to warm up. heyhusky.com

• Sleep under northern lights
  Two chalets in the middle of Lapland's nature: "Octola Lodge" is the most exclusive hostel in the area and attracts with untouched wilderness. octola.com.