DILLING Underwear tested on Kilimanjaro

At DILLING, we believe that our woollen underwear will keep you warm wherever you are. Therefore, we recently sent four sets of long woollen underwear to Tanzania with Jan and Mikkel to test whether it kept them warm on their trek up Kilimanjaro.


Father and son tell the story

Just two weeks before our departure, our bags were packed full of gear and expectation, and then a package arrived in the post. The parcel was from DILLING, containing two sets of exclusive merino wool ski underwear alongside two short sleeve organic merino wool base layers. We received the clothing to test whether it would keep us warm, dry, and comfortable whilst climbing Africa’s highest mountain, Kilimanjaro.

Standing at 5895 metres, Kilimanjaro is the highest free-standing mountain in the world and also one of the ‘Seven Summits’ (the highest mountains of each of the world’s continents). Reaching the top is a technically difficult and challenging trek. The journey starts at the foot of the mountain in an altitude of 1833m, and on our way to the top we trekked through five different climate zones. This is the equivalent of going from the Equator to Antarctica in seven days. Due to the speed at which the weather at high altitude changes, it is demanding on our gear and our clothing.

The first day of our hike started at Machame Gate where we had a 5-hour hike up through increasing altitude. As we made our way through the jungle, the temperature was 25 degrees and the humidity was very high. To avoid sweating too much in the heat and getting dehydrated, we both decided to start the trip in a regular 100% polyester running t-shirt. Generally, the top was fine and breathable, but when we sat down in the shade we quickly became cold in the damp t-shirt. Therefore, we decided to change into the merino wool short sleeve base layer, which whilst it still got wet, we stayed warm. Unlike cotton and synthetic materials, wool keeps its insulating abilities even when wet.

The following three days were spent almost entirely in our short sleeved woollen shirt, when it varied between 5 and 20 degrees. When it was windy, we simply supplemented it with a wind jacket. The base layer kept us warm close to our body.

Although the temperature during the day fluctuates between 20 and 25 degrees, the nights in the mountains are very cold. The first night was spent at already an altitude of 3100m, therefore we decided to put on our ski underwear (long sleeves and full-length bottoms). This skiwear felt softer in quality than the normal organic underwear. This is not because our organic underwear is itchy, it’s far from it as you can wear it on bare skin, but because the wool fibres in the skiwear are so fine you can barely tell you have it on, it’s that good! It also fits snugly against the body, making it even more comfortable when, like us, you have to spend the night in a sleeping bag and liner, and too many loose layers can be irritating and cause you to lose sleep.


As we gradually reached higher altitudes, the vegetation changed, and the temperature began to fall, so we put on our organic long johns as a foundational layer under our light trekking pants. They were incredibly insulating and because we were so active, we even had to occasionally roll up our trekking pants to cool down our legs.


Before we left to come away, we packed our bags with lots of different items that we thought we would need. We soon found out that an organic merino wool base layer combined with a high-quality pair of trekking pants and a shell was plenty.

It wasn’t until the 6th night when we had to hike to the top that we decided to layer up. The temperature as we approached the top was around -12 to -14 degrees and the wind was cold too, therefore it can get as low as -25 degrees. We put on the tight-fitting skiwear first, close to our bodies, followed by the looser organic underwear on top. Finally, we put on our normal ski jackets and pants.

The first part of the trip wasn’t as cold as we expected and we both began to sweat. Despite wearing two wet layers, the wool’s unique properties meant we didn’t feel the cold at all. In fact, it was only Mikkel’s feet that felt the cold when we reached 5500m above sea level and it was gusting wind.

Once back at a lower altitude, we evaluated the performance of both sets of underwear:


Both sets had excellent insulating properties and had great breathability. We were never cold, and although we were physically active and sweating, the dampness was quickly wicked away from the body. As a base layer both sets were fantastic and when combined with a pair of high-quality hiking pants and a shell-jacket, our body temperature was quickly regulated according to our surroundings and activity level.


The seams and joining sections of both sets of clothing were secure and not noticeable. The products also seemed robust and had a high level of elasticity. In relation to the fit, the organic set fitted more loosely, whereas the ski set had a tighter fit. Both set of bottoms were fitted with a fly, which you appreciate when it is -7 degrees in the middle of the night and you need to go to the loo.


There is also a whole at the end of the sleeves on the ski set for your thumbs, so the sleeve won’t ride up your arm underneath your jacket. Clever! The comfort when moving couldn’t have been better and both sets were very soft and comfortable, although the wool fibres in the exclusive set felt slightly softer.


We previously mentioned that merino wool has exceptionally good warming and moisture-absorbing properties, and we have also heard it helps reduce smelly odours, but the fact that even after 7 days of us not having had a bath, it barely smelt at all, and that surprised us!



Donation to the team


Lastly to mention, there was one thing that surprised us both on our way up Kilimanjaro, and that was the conditions for the hundreds of porters that carry the tourists’ heavy luggage and equipment from one camp to the next each day. These (mostly) young people, work the hardest on the mountain while the rest of us hike to the top in highly- technical and smart hiking gear. The porters usually wear jeans, cotton t-shirts, and worn out plimsolls, which is far from ideal. Proper clothing in Tanzania is expensive and difficult, therefore the mountain workers (porters, cooks, guides) depend on donations from tourists. These includes money as well as gear itself. At the end of our trip, we gave our mittens, woollen socks, beanies, thermal underwear, neck warms, and of course our DILLING underwear, to the workers.

If you suddenly spot someone wearing DILLING on your way to Barafu Camp, you’ll know that person isn’t cold!


//Jan and Mikkel Hilgart



Thank you to Jan and Mikkel for their great report. You can see the products they tested below:

Men’s merino wool leggings with fly- black
Men’s quarter length merino wool shirt- black
Men’s non-itchy merino wool shirt
Men’s merino wool shirt
Men’s woollen underpants
Men’s woollen shirt