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☆ How to prepare for a Polar expedition

During the winter of 2020, right before COVID hits my country, I spent 17 days (almost) alone in the Arctic. I was 21 years-old at the time, and already spent a decent amount of time skiing in the snow and in the cold. But this experience was life-changing, not only in terms of learning, but also in terms of self-discovery.

Recently the brother of a good friend of mine contacted me because he’s planning to do something similar, but has zero experience in this kind of adventures. Has he come with tons of questions, I told myself that maybe it is a good time to share all things I learned planning and doing this trip in a more “public” way. It is also a good opportunity to go back into memories of snow, cold, pain and fascination.

Disclaimer: I have experience with European Arctic conditions, so please take those advices carefully and with precaution as they may not apply to where you’re going. Going to the Arctic circle in Sweden is not the same thing at all than going to the Arctic circle in Canada for example.

Planning the trip

The track

I planned to ski along the Kungsleden, literally the King’s Trail, in the Swedish Lapland. This is a ~450km/10000m D+ trail that goes from Abisko to Hemavan, above 66° north of the Equator and through the Sarek National Park. This trail is pretty famous among hikers and backcountry practitioners, but as fair as I know, not a lot of people did it completely, on their own.

The most know winter route on the Kungsleden is the one that goes from Abisko to Nikkaluokta, via the Kebnekaise (Sweden highest mountain). I did it in 2015 when I was 16 with my father and brother. It is a relatively short and flat trail (~100km/1300m+) with a lot of huts and cabins where you can sleep if you pay. Doing it may take 4 to 8 days, depending on the weather and your physical condition.

My goal was to do the full Kungsleden in 30 days, for an average of 15 kilometers a day in the worst case. The idea was to do more than that in order to have some security days when you can do nothing except staying in the tent waiting for the bad weather to pass, or recovering from an illness or an injury. Those security days are pretty important because you’ll definitely have days when progressing is not an option.

I also planned two rest days: one at Saltoluokta after the first week, and another one at Jäkkvik after the second week. I chose those places because it was possible to have a warm shower and rest in a heated cabin.

For those of you that are interested, here is the .GPX file of the Kungsleden trail, with some minor adjustments:

You can open it in tools such as or Google Earth (if you convert it to their shitty KML format first).


Choosing the right period of time to do your expedition is crucial: if you go to soon in the winter you’ll experience really low temperatures. The coldest night I had was around -40°C (which is also -40°F, funny!), and it was in March! You’ll also experience shorter days and longer nights.

On the other hand, going too late in the winter have some serious drawbacks too. Around mid-March, the temperatures start to go above 0°C (32°F), snow starts melting and lakes unfreeze which can be quite dangerous as you’ll cross many of them during your trip. Also, progressing in a melting snow is really awful when you’re on skis. The snow sticks to the skis, and it is really, REALLY hard to go forward.

I left my house on February, the 28th to start skiing on March the 1st. I probably should have started a little sooner as mid-March the snow started melting.

What’s important to note is that it’s very complicated to do such of a expedition before mid-February, as the days are really short, and the cold is really biting. Beginning of winter (late October/November) is when the days are shorter, and the snow conditions are pretty instable too.


I decided to go the Abisko by train only, for multiple reasons:

  • I’ll be heavily loaded. Some people send their pulks to Abisko’s post-office and get them back when they arrive, but there is a non-nil chance that your stuff will break during the travel. So I decided it will be better to carry my pulk from train to train.
  • I need to carry liters of flammable fuel. In order for the stove to work, I need to bring with me a decent amount of gasoline. For obvious reasons, you can’t carry liters of fuel by plane, so it was not an option1.
  • Enjoy the process. Travelling by train has something special, and I enjoy it. You can chill and enjoy the view.

Going to the North by train isn’t so expensive when coming from Europe: from Basel to Abisko, it cost me around 180 euros, but I had to change trains 4 times: in Hamburg, Copenhagen, Stockholm and Gällivare.

In the Abisko and Gällivare areas, it’s quite easy to move with public transportations like buses, even during winter.

The equipment

Pulk and skis

Pulks are a wide subject. I found an excellent guide with good ideas here: Rigging a Pulk the Right Way by the Fortune Bay Expedition team. They say it all.

For the skis, I went with a used pair of Sporten Ranger 68 with Rottefella Super Telemark 75mm, classic stuff for this kind of trip.

What I like with those bindings is that they are easy to repair if they break: for most issues, having a few centimeters of hardwire does the job. However, in the long run they can wear out and damage the shoes. Also, the foot flexion is not very natural, that’s why I tend to prefer the new Rottefella Xplore bindings nowadays.


Clothing is really important, but the same general rules apply: use 3 layers.

The first layer should be worn nest to your skin and be breathable to evacuate moist and sweat. The second one is here to keep you warn, and the last one to isolate you from the wind, rain, and other elements.

You may want to add another layer, which is an insulated jacket (preferably insulated with feathers like sleeping bags) for when you’re at the camp.

So nothing brand new here if you’re used to trekking, but just keep in mind that you must not sweat!


The camp is basically your house. You want to keep it safe and warm, as you may spend full days inside (due to various health or meteological reasons).


For this expedition, I bought a dedicated tent (almost 50% of the trip price was the tent!). I went for the MSR Access 2, and purposefully bought the 2 persons model, because having some space is important in such conditions where you can possibly spend 24 hours inside. It cost me around 500€ (with a discount) and weights 1860 grams. To be honest, I think this tent is unbreakable. It went through hard wind, heavy snow, and since then I brought it in various hikes and trip in the mountains and it is still in perfect condition. I generally think that MSR does great products, and this tent is the perfect example.

You should bring with you a little brush to attempt to remove all the snow from your stuff to avoid getting wet in the tent. But I’ll emphasize on this in the next section.

Another way of sleeping in the Kungsleden is going to STF huts and mountain cabins that are, for most of them, guarded and not free of charge. If I recall correctly, it costs around 45€ per night per person for an adult, and you must pay a membership before the first night.

Sleeping bag

Before talking about the technical aspects of sleeping bags, you have to know and keep in mind something crucial: if your sleeping bag gets wet, you’re done. You must avoid at all cost to bring snow and/or ice inside it, even if it’s in a solid form. It will melt during the night, and you’ll end up absolutely cold. Also, when you’re spending days and night inside a freezer, you can’t dry your stuff. You must be really careful about it as it can stop your expedition pretty fast.

About the technical aspects, I went with the Sir Joseph Looping 1200. It supports quite low temperatures (-18°C comfort, -54°C extreme), but the trade-off is the weight: around 2kg so heavier than my tent.

I spent a few nights with the temperature dropping below the -30°C. Breathing air that is around -40°C is painful. After a while, it starts to burn your throat, and you cough all the night. But you must try to always breathe out of your sleeping bag to avoid accumulating humidity that will freeze/unfreeze during the night.

Sometime, your sleeping bag will not be enough to keep you warm during the night. Be smart about which layers you keep on you, and avoid sweating at all costs, for the same reasons listed above. Wet stuff is one of your worst enemies here.

During winter, the first part of the Kungsleden is well-indicated with big red-crosses. Most of the time, you just have to follow them and having a compass and a map are more than enough. However, if you plan to go off-track, having a GPS can be a good idea, unless you’re pretty comfortable with the map.

Personally, I went with both the compass/maps and the GPS (an old Garmin Oregon 450), but I almost only used the maps. Navigation there is not so complicated as you either have to follow the red crosses, or follow valleys. But keep in mind that if the blizzard comes, you’ll no longer see anything beyond 2 or 3 meters and can easily get lost. Such meteorological events happened twice during my trip, and it was quite scary.


I brought with me a SPOT Satellite GPS Messenger (this one) with me, but they are no longer sold. Given that the Kungsleden is not really far away from the civilization, and some areas are quite frequented, it’s enough to be safe in case of emergency.

I’d still advise you to inform the local authorities of your presence, and to send them a photo of you and your equipment so that they know what to look for if necessary.

Also, even if you do not plan to sleep in a SKF Hut, you might still want to inform the warden about your plans.


In addition to what has been said above, here is a non-exhaustive list of things that you probably should take with you:

  • Emergency blanket: this can literally save your life. You must have one in any hike or adventure you take part to.
  • Sewing kit: for your clothes and yourself. Learning the basic surgery knots can be helpful.
  • Multitool: the Leatherman Wingman my parents gifted me before my trip happened to be really helpful.
  • Repair kit: hardwire, tape, screws.
  • Extra batteries: the cold sucks every electron of your batteries at a demoniac speed. My camera’s battery lasted for 2 to 3 days before needing to be recharged.
  • A shovel to dig holes and

Cooking and Drinking

Stove and fuel

In my opinion, the stove is the only single point of failure of such expedition: if it fails you cannot drink, and you cannot eat, you’re not going to last for a long time up there. It is critical to have a reliable stove that you maintained and checked before leaving. I did not do that and mine clogged up on the second day, making it difficult to use until I could clean it properly.

I went for the MSR Whisperlite, and if you take care of it, it works pretty well.

You stove needs to use fuel, as with such low temperature gas cartridges empty quickly as you only burn half of the content (with low temperatures, the mixture of propane and butane separates, and you burn only one of the gases leaving the cartridge half-empty and useless).

A big warning here: using a stove inside your tent is very risky: when you light it on, it usually does a moderate to a big flame that can burn your tent down extremely quickly, and you end up homeless in the blink of an eye in a place where you do not want to be homeless. Also, if your tent is not sufficiently ventilated, you may breathe toxic gas and have big troubles.

Personally, I cooked almost exclusively outside as you can see in the picture below. If wind is an issue, build a small ice wall around the stove to protect the flame.


Even if the temperatures are quite low, you’ll need to drink plenty of water each day. Most of your water will come from water you’ll melt using your stove. Once the water has melted, you have two choices:

  1. Bring the water to a boil to ensure it is safe to drink.
  2. Use pills such as Katadyn’s Micropur.

I personally went with the latter as it’s easier, safe and needs less fuel. But even if the snow is immaculate white, do not drink it as it. There are some animals, and even humans. It’s better to be safe than sorry (to your stomach).


Damn, there’s a lot to say here as I did two big mistakes: I bought food that was not adapted to the environment, and I planned to eat hot only once a day.

About the food I chose, I wanted to go cheap. I bought classic hiking stuff such as packet soups, semolina, cheese and meat like salami. As you probably think, this is not enough calories for such a cold place. Also, sometimes the temperature goes above 0 degrees so your food freezes and unfreezes many times, so I ended up being sick. But most of the time, the temperature is below zero so cheese and sausage are literally impossible to cut and eat. Due to those poor choices, I lost more than 5 kilograms in only 17 days, and was really weak.

About the hotness of my food, eating cold food during the day is a bad idea. Everything that’s warm is more than welcomed. Of course, I thought about it and decided that carrying extra fuel for this was not worth it. But oh boy, I was wrong. Eat hot food at each meal.

The solution to both of those issues would have been to spend more bucks on lyophilized food, and prepare my hot lunch in the morning while I’m boiling water for my coffee.

Physical preparation

Of course, you need to be in shape and a bit trained before taking part of such adventure. Running a few times a week can be a pretty good starting point if you stay in your endurance zone. Hiking and doing trail running can be good to also train for uneven terrain and hills.

The more kilometers you’re able to do on foot, the best. But do not neglect upper body muscles. You’ll find yourself lifting and pulling your pulk with your arms more than you thought.

Weeks before my departure, I went running once a week with 2 to 3 car tires attached to my pulk harness (sadly no pictures) for 45 minutes to an hour, to train my back and get familiar with having something heavy pulling me back. I think that it definitely helps.

Overall, for such a trip and if you already do some sports (one or two times a week), training during two to three months should be enough. But who can do more can do less. :)

About failure

There is a popular saying, inherited from the Apollo 13 movie, that says “Failure is not an option”. In the context of polar expedition, let me tell you that it is, and you should also be prepared for. Hope for the best, prepare for the worst.

As you probably understood if your read this whole article, I did not finish my expedition, for multiple reasons.

First, being alone in such rough conditions is hard. You’ve nobody to talk to, and nobody to help decide what is the best thing to do when you’re stuck. Is this lake safe to cross? Will this block of ice and snow collapse when I’ll be on it? You have to decide, and no none will prevent you from selecting the wrong option. You have to assume your choices, and doing such decisions all day long is quite exhausting.

Second, COVID. When I left in February, I had never heard about COVID. On March, 17th, my country was locked down.

Lastly, my gear and I were broken. I did not train enough, lost a glove, broke part of one of my skis, my sled ropes were horrible in both downhill and uphill: despite being quite experienced, I was not prepared enough. Those trips can’t be improvised as so many things can and will go wrong. Bodies, minds and gear are pushed to the limit, and they all have to be ready. In my case, they were not. I tried to make my expedition as cheap as possible, and it was a mistake: my food were almost impossible to eat in those conditions and I could not melt enough water which weakened me and I ended up being sick for the first week.

Key takeaways and ending word

If you have to keep in mind a few things before starting your own journey, here they are:

  • Do not trade safety for money.
  • Avoid being wet at all cost.
  • Pareto’s principle also applies: planning is 80% of the expedition.
  • Know when to stop. I once read somewhere that dead bodies on the Everest all were highly motivated individuals once.

I hope you found some good information here, or at least you enjoyed the pictures. Of course I probably forgot a lot of things as there’s a lot to say! So if you think about something or have a question, or even if you just want to chat about such trips, drop me a line at this email address.

Take care! ❄️

  1. In theory, you can buy fuel at the Abisko pump station at your arrival. However, if the station is empty, you’re doomed. ↩︎