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Three Things To Know:
- Incredibly light weight - at only 320 grams
- GORE-TEX lining - keeps feet dry but is also breathable
- Suitable for mountain training - with reliable grip and just enough ankle support
Our Rating:
Comfort and Fit
Waterproofing and Weather Resistance
Durability and Materials
Weight and Flexibility
I picked up the Mammut Sertig II Mid GTX boots after a string of soggy, uncomfortable hikes in shoes that just weren’t cutting it anymore. I wanted something lightweight, waterproof, and supportive, but not stiff or bulky.
Right out of the box, these felt different. They’re sleek, flexible, and felt more like a trail runner than a traditional hiking boot and are great for fast hiking. After wearing them on a few damp, rocky trails, I had a pretty clear sense of how they hold up, and I was pleasantly surprised.
weigh only 320 grams
Comfort and Fit
From the first time I laced them up, the Sertig II Mid GTX felt more like a cushioned running shoe than a hiking boot, which was exactly what I was hoping for. The fit is snug but not tight, with just enough room in the toe box to avoid pressure on descents. I didn’t have to break them in; they were comfortable on day one.
The ankle support is there, but it’s not overbearing, which gave me a good range of movement on uneven ground, making these boots good all-rounders. Even after a full day of walking, my feet felt fresh, no rubbing, no hotspots, and no sore arches.
Due to how lightweight these boots are, they don’t offer the same level of protection or structure as heavier leather, so if you have issues with your ankles that’s something to consider.
Waterproofing and Weather Resistance
I wasn’t sure how the waterproofing would hold up on these, however the GORE-TEX membrane kept my feet dry splashing through puddles and shallow streams, and on muggy and hot days the breathable mesh kept my feet from overheating.
The breathable mesh is a huge plus when weather is unpredictable, and combined with the waterproofing makes these boots a great all-year-round option.
After a few hours on soggy trails, my socks stayed dry and I didn’t get that sweaty, sealed-in feeling. I wouldn’t take them through deep streams, but for damp hikes, muddy paths, or drizzly days, they’ve proven to be a reliable shield against the elements.
Durability and Materials
At first glance, the Sertig II Mid GTX boots looked almost too lightweight to be tough, but after several hikes on rocky paths, loose scree, and wet trails, they’ve proven sturdier than expected. The synthetic upper resists scuffs well and cleans up easily, while the sole still looks barely worn despite some decent mileage. The stitching and bonded areas feel solid, and the toe cap has protected against more than a few accidental kicks into stones. These aren’t built for hardcore alpine scrambles, however, Mammut claims that they’re durable enough for mountain training which I agree with, and for regular hiking and mixed terrain, the build quality feels reassuring and built to last.
Similarly, the upper, while breathable isn’t the most rugged and might not hold up to serious use and abrasion over time.
Weight and Flexibility
I was excited to try the Sertig II Mid GTX because of their ultralightweight. Weighing 320 grams, they’re incredibly light for a mid-height hiking boot, and that difference is noticeable right away. I don’t feel like I’m dragging my feet uphill, which makes longer walks a lot more enjoyable.
The flexibility in the sole and upper also gives them more of a trainer-like feel, without losing the ankle support I want for uneven trails. They bend naturally with my foot, which really helps on steeper climbs or descents. If you’re after lightweight comfort without going full trail-runner, these hit a great middle ground.
Grip and Traction
The Mammut Swiss Design sole performed well on a variety of different terrains, from dry gravel paths to muddy forest tracks and slippery rocks, and so far has been consistently reliable.
The sole pattern gives good bite on loose ground, and I felt confident descending steeper slopes without slipping. It’s not the most aggressive tread out there, so for really wet, technical terrain I might reach for something burlier – but for day hikes, mixed trails, and everyday use, they’ve held up well. I especially like how the sole doesn’t clog easily with mud, which keeps the traction more consistent across changing conditions.
Value For Money
At £155 these are quite expensive, however, for such a lightweight boot are impressively durable, comfortable and waterproof.
Sustainability
With an impressive repair policy, Mammut repaired 15,000 products in 2024, and have also implemented LOOPINSULATION – converting rope production waste into insulation material, cutting emissions by 48% compared to virgin polyester.
Should You Buy It?
If you want an ultralightweight hiking boot with impressive durability, versatility and comfort.
SQUIRREL_13245733
Find more in our guide to the best walking boots.
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