Aku Alterra GTX boot review

Aku Alterra GTX Boot

There are some brands whose individuality seems to shine through in every product.  The ones where you see their garments or footwear in the shop and just know, without even seeing the labels, that they are made by that particular company.  Aku, for me at least, is one of those brands.  Maybe one designer works on all their models or they have a particular design brief to work too.  I don’t know how they do it, but they do.  I’m not saying this is a bad thing though because all the Aku footwear I’ve seen and tried in recent years has been both great looking and top performance – and on both counts the Alterra GTX boots are my very favourite Aku product so far.  The Alterra GTX are a brilliant boot in every way…..


Aku market the Alterra GTX as a boot suitable for ‘medium difficulty and duration trekking over mixed terrain’ and so the feature set is specifically designed around that brief.  The upper is made from suede with a synthetic stretch material on the heel cuff and tongue PU wear protection around the toe and heel.  The lasting board is made from nylon with die cut EVA to give medium stiffness and the midsole is PU with a Vibram Octopus outsole.  The Alterras also feature a Goretex performance comfort sock and there’s a custom fit footbed.  

It is the sort of comprehensive feature package I’ve come to expect from AKU and yet many premium quality boots may boast similar specs – is there enough about this package to set them apart?

In Use

I have been using the Alterra’s for several months.  This period crossed from the tail end of winter when I spent plenty of time yomping the boggy Peak District moorland on navigation and mountain leader courses through to the hot and dusty terrain of the Picos De Europa in northern Spain.  The weight carried has varied from a rucksack packed up for several mountain days through to a light day sack.

From the first try on I guessed these boots would become a tried and tested friend, and this has been confirmed more and more with every use.  The key to this amazing fit is due in large part to the stretchy tongue which moulds around the foot and means a tongue gusset isn’t needed.  It cradles the foot brilliantly, feels fantastic and also makes lacing the boots a breeze.  It is the type of design you will more likely find on running shoes and I’ve certainly never tried boots with this feature before – but it is a great design which makes the Alterras fit like gloves.  

Aku boots really suit my foot shape and, of course, it is essential that any potential purchasers ensure they fit theirs too.  Having said that, I do think Aku’s specialist knowledge as a dedicated footwear company shows in the overall fit of their products. I have now reviewed a very varied selection of their offerings (my Mio GTX shoe review is here, Superalp NBK GTX boots review is here and my Bellamont Plus shoe review is here) and every one has been a superb fit. 

The Alterra’s have stayed comfortable on even the longest mountain days and I think this is very much down to their careful midsole/outsole choice.  The medium density midsole works a treat for challenging ground – I have hopped through the boggy Kinder groughs and tabbed gravel mountain tracks in Spain with a heavy climbing pack and felt comfortable every time.  I have no doubt this boot will become a faithful companion for everything from day hikes to multi day backpacking adventures.

I was also immediately impressed by the edging capability and lateral stability of the Alterra’s.  I knew they worked well but had to delve into the technical info to find out why.  Aku have used an asymetrical outsole with what they describe as ELICA technology.  This is designed to provide even load distribution and improve foot roll, and it really does work exceedingly well.  They would make a great easy to mid grade scrambling boot just as they will keep your foot laterally supported crossing steep grassy slopes.   

The Vibram Octopus outsole has a rugged and deep tread pattern that has certainly coped well with everything I’ve thrown it at.  While wet and greasy limestone in Spain tested it (but would also stretch the grip of any sole unit), on everything else they have gripped well and the tread pattern has cleared debris well too.  I noticed this in particular during tests on gloopy moorland peat which, despite loving to stick to things, was soon thrown out of these sole units.

Having a Goretex sock ensures waterproofness and there has certainly been no leakage to date although keeping water out is also undoubtedly aided by the durable suede upper.  I was concerned with how waterproof the flexible tongue material would be but again no problems at all to date.  Aku are renowned for rigorous testing of their footwear in all conditions and, as well as valuing that ethos, I feel it provides a very well rounded and trustworthy product.  

The Alterra’s have a protective rand around the toe and heel and so far this has ensured any sharp rock or other damaging terrain obstacles have been easily kept at bay.  I was surprised Aku didn’t continue this around the centre parts of the boots, but there certainly hasn’t been any wear problem in these areas and so I guess they know what is needed better than an opinionated reviewer like me! The rand is a solid PU material and looks like it will cope with plenty of terrain abuse.


And so, as you will have already gathered, I believe there is everything to love and nothing to dislike about the Alterra’s.  The usual Aku quality and attention to detail mixed with some fantastic design features and innovative additions.  This is a great boot for everything from multi day backpacking to scrambling and, while perfect for the challenging UK climate, they will keep your feet comfortable in warmer and drier conditions too .  The cost of the Alterra is £180 and their stated weight is 670 grams. Further details are available on the Aku website here and the short video below explains the ELICA system.

Posted by Paul