Mammut Alnasca Knit Low GTX Shoe Review

14th Nov 2018

Mammut Alnasca Knit Low GTX Shoe

I am, without question, a frustrated equipment designer.  As much as I would never change my mountain guiding job, I do love to tinker with equipment and assess the design process that went into each items production.  And, of course, we are very spoilt for choice nowadays.  The creative minds of talented designers mixed with technically advanced materials and production methods allows companies to churn out some amazing products.

Mammut are a company that I have always felt to be at the top of the creative pile.  From their super advanced clothing to the innovative climbing hardware, rucksacks and ropes, they are undoubtedly industry influencers and keep churning out some amazing products.  

Besides all this, they also produce footwear and it has been a pleasure to use a number of their boot models in recent years (I wrote an in-depth review of their Ayako here). But one Mammut product type that had so far escaped me was their technical approach shoe models - and I was keen to put that right.  Fortunately, the arrival to market of their Alnasca Knit Low GTX shoe was the perfect opportunity and Mammut kindly sent some across for review......


Going back to my observations about being a frustrated footwear designer, the Alnasca would be just the kind of shoe I would have loved to work on - it is a very attractive and technically advanced shoe.  I was sent the option in black and citron (yellow to you and me) which combines yellow tongue, laces, midsole and heel cuff alongside dark grey and black outsole, rand and main body.  It is a striking combination that works really well together. I should also say that Mammut also produce a black/blue colour combo which you should also check out. You won’t spend all this money to just wear the Alnasca to the pub, but it certainly is smart looking enough to comfortably transfer from the mountain or crag right through to apres climb activities.

Infact, thinking a bit more about its uses, Mammut market the Alnasca as a shoe designed for ‘unpredictable mountain conditions’ and I have to be honest that I didn’t really know what that meant - unpredictable weather, terrain or activities?  I decided they probably meant a bit of each and, as many of us now partake in a broad range of mountain activities and the weather can certainly be variable, this kind of makes sense.  

To achieve this multi-condition capability the Alnasca’s feature some very advanced technology.  Starting from the ground up there is a Michelin OCX Approach Rubber compound outsole designed to cope well with everything from slippy grass to wet or loose rock. It strikes a balance between stiffness and the flexibility required to offer good friction and a medium deep tread pattern which should cope with mixed terrain.  The outsole toe box also has a solid climbing zone offering good edging capability.

The midsole, again coloured in that striking yellow, is made from a dual density material designed to offer the balance between comfort and support.  Added to that, the support and rigidity is then added to by a board lasting, anatomically shaped footbed and TPU heel insert.  

Besides all that, the fit and support of the Alnasca is aided by other key features.  Mammut have added ‘360 degree heel support’ which is a protective and supportive 3D heel cup designed for the anatomy of the heel bone.  This offers protection from rock abrasion while also providing lateral support to minimise the risk of twisted ankles.  

The upper part of the shoe is just as innovative.  To stay with the heel unit for a moment, Mammut have added their Base Fit system whereby sliding webbing transfers power from the lacing system and through the sole unit.  This pulls the heel into the heel cup and thereby holds the foot securely.  I had loved a similar feature on the Mammut Ayako and so was really interested to see how I found it on these shoes.

Mammut have used a durable PU rand around the sides of the Alnasca along with a solid and protective toe box.  Above that is the rather special 3D knitted vent mesh sock which forms the rest of the upper.  As the name suggests, this is indeed a tough and stretchy ‘sock’ which you slide your foot into.  It offers a supportive and snug fit which eliminates bulk and effectively moves with your foot to provide a very comfortable yet efficient fit.

To offer mixed conditions functionality the Alnasca has a waterproof Goretex Performance Comfort liner and elastic Goretex tongue construction and the Alnasca features a traditional lacing system.  

The use of these high tech materials also gives the Alnasca a low weight of 380grams for a U.K. 8.5.

In Use

The Alnasca is new to market and so I haven’t had them long enough to do a full durability test, but I have put them thoroughly through their paces.   I am writing this review on the way down from Everest Base Camp and the shoes have been my daily footwear for the last few weeks of trekking plus before leaving for Nepal I had time to use them for some gritstone scrambling and a lap on the Winnat’s Pass limestone scrambles near my home. Certainly enough variety to comment thoroughly on their performance in different typical situations. 

So, to dive in there straight away - I really can’t over emphasise how much I like these shoes.  From the first try on until now they have felt really comfortable and they have proved extremely competent at absolutely everything I’ve thrown at them.

Pulling the feet into the knitted sock upper is easy (there is a pull on tab at the back) and once they are on it really feels like you are wearing a pair of comfy slippers.  Slippers, except that the supportive heel cup and protective low profile toe box offer a feeling of support and solidity.  The knit construction and elasticated tongue also ensures the shoe feels very low bulk which is an important consideration when using them for activities like scrambling, low grade climbing or via ferrata. 

Once you pull the laces tight you can really feel the Base Fit system pull your foot in snugly.  They feel both supported and comfortably locked in place. I should also mention that the lacing system is constructed to be very low profile - the laces link through a series of tape loops with the top ones looping through the attachments for the Base Fit system (the top two of which thread through some very neat self centring plastic rings.  It is all efficient and low profile enough so that nothing gets in the way for technical activities.  

I also really like the shape of the Alnasca.  The toe box, while plenty roomy enough for my normal to broad width foot, still has a low profile shape that puts power through the toes and offers enough support for standing on smaller edges or dipping the toe of the shoe into pockets when ascending technical ground.  As mentioned, I took the shoes for a lap of the Winnat’s Pass classics Matterhorn and Elbow Ridges and they felt precise, secure and edged extremely well.  Mammut say the shoe will perform well on via ferrata and, although I haven’t had chance to test this yet, I have no doubt they would also be great for this activity.

My Nepal trek allowed some opportunities for me to test out the waterproofness when caught out in one or two afternoon showers and my feet stayed dry, but I certainly can’t claim this was a thorough test of the Goretex insert. I will get more chance to report back on this after more time in the Peak District autumn and will update the review accordingly.  I have, however, used other shoes with the same type of waterproof sock with good results and so feel confident they will perform well.

In terms of long term durability it is hard to comment yet.  The Alnasca has shrugged off some vertical adventures and a few weeks trekking without any signs of wear and tear and so I am confident they will stand up well to longer term use.  However, I will really need to also comment on this somewhere down the line.  I do applaud Mammut’s selection of materials highly.  The solid heel and toe box feel very substantial and this is backed up by the durable PU rand that surrounds the lower part of the rest of the shoe. They also, like all Mammut products I’ve used, look incredibly well made with superb attention to detail and craftsmen like build quality.  Yep, I feel sure they will be a great long term companion.  


I have not hidden for a second that I really like everything about the Mammut Alnasca Knit Low GTX Shoes.  They look fantastic, perform superbly and look well built enough for many mountain adventures.  They are also a very versatile shoe that will suit many users in many situations.  Many outdoor activists nowadays dip into lots of different branches of the sport and so there is more need than ever for shoes that tick plenty of boxes and the Alnasca does that with aplomb.  At a retail price of £149 they are quite a weighty investment, but you are certainly getting a lot of shoe for the money.  Another great product from Mammut and another example of the skills of their designers - I only wish I could have designed these myself!

Posted by Paul