We’ve put together a list of what we think are the 4 best rucksacks for mountain activities for the spring/summer season. Take them high level walking, scrambling, rock climbing, or on an Alpine route, and we think you’ll agree, these four are certainly among the very best buys available.

In our test we tried each of the four rucksacks selected in a number of different mountain ranges, and for a variety of different activities. They all went out on gentle hillwalks, a handful of scrambles, and on a few long mountaineering climbs. All but the Osprey Mutant were also tested on winter ground (the Osprey arrived a bit too late in the season for that!)

For each rucksack we wanted to test a number of things:

  1. How practical was the size of the sack for the activities?
  2. What was the comfort of the sack like with a full load?
  3. Was the rucksack functional in cold and testing weather conditions?
  4. Did the rucksack ‘work’ for all the activities it was used for?
  5. Was the overall design to our liking?
  6. As these were all sent as an ‘Alpine, light-weight sack’, was each rucksack functional at the weight?
  7. Value for money?
  8. Outstanding features?
  9. Anything we don’t like?

So, here they are. Our mountain pack top pics!


Osprey Mutant 38

A great rucksack absolutely packed with features.

  1. Practicality. At 38l not the biggest of the sacks tested, but a good choice for scrambling and rock climbing routes. We used it on a number of low-grade, long mountain routes, and found it big enough to put all our spare gear in, food, water, and walking boots while we were actually climbing.
  2. Comfort. Not a brilliant back system, but actually just right as a light-weight sack. Certainly more than adequate in the comfort stakes. Well padded shoulders.
  3. Functionality in bad weather. Not tested in winter conditions. In heavy rain, the twin lids on this pack actually became a bit of a faff, and the draw-cord on the sack top was fiddly. The side compression straps have to be adjusted at both top and bottom, with the top buckle actually having a release catch. This could not be undone with gloves on.
  4. Use across a range of activities. I’ve used the Mutant for scrambling, rock climbing, and general hillwalking, and it works well for all those activities. There is a detachable lid, with a second top cover, and this worked very well for ultra light-weight scrambling or walking when the lid with its large pocket could be taken off altogether. The waist belt has gear racks in a good place for climbing kit, and the lid has a helmet pocket too.
  5. Design. Overall, a good, clean design, though some won’t like the vivid yellow colour. Good use of gear racking systems, and a reasonable length chest strap too.
  6. Weight. 1.19kg
  7. Value. RRP – £100.
  8. Outstanding features. Detachable lid, giving an ultra light-weight option for fast ascents.
  9. Let-down features. Fiddly straps and closure buckles with gloves.


Millet Trilogy 30

An eye-catching sack, part of the Millet Pro-Lighter range.

  1. Practicality. At 30l we found the Trilogy to be just about big enough for most activities. We used it for winter mountaineering and rock climbing, and could get most gear into the sack for the walk-in, but ropes and helmet had to be strapped to the outside.
  2. Comfort. Not the best back system, and the shoulder and waist belts could do with a bit more padding. For winter use this hardly matters as the extra layers of clothing you wear mean that padding is less important. As this is intended to be a very light-weight pack, these comfort features are among those that Millet have highlighted in order to reduce the overall weight of the rucksack.
  3. Functionality in bad weather. All the buckles and straps are large enough to be functional with winter gloves on, although the pull-cord on the main closure was a bit faffy. The buckles for fastening down the lid are fixed too high on the rucksack body, which leaves the lid very loose if the sack is not fully loaded up.
  4. Use across a range of activities. A bit of a no-nonsense rucksack here, which is a good thing I think. It worked well for most mountain activities, but I could possibly have done with a slightly larger version for winter use – it’s ok for personal use, but for anyone working as a guide or instructor you don’t have room for any extra kit. Gear loops for climbing hardwear on the waist belt are in a good place for racking kit.
  5. Design. A bright, colourful design, which might turn some people off. Well thought out with all the gear-racking positions, apart from the main buckle straps. A good-sized chest strap too!
  6. Weight. 1.04kg
  7. Value. RRP – £100.
  8. Outstanding features. Light-weight and relatively simple design, but with good features were needed.
  9. Let-down features. Main lid closure buckles are set too high on the sack body, which gives the rucksack a very scruffy look when it’s not fully loaded.


Lowe Alpine Mountain Attack 45:55

A lot of quality pack for your money. 

  1. Practicality. At 45l with a further 10l in the lid, this is a big sack this one, and great for longer routes in any weather when more gear might need to be carried. I used it for winter mountaineering, and summer backpacking too, for which it was the best in test by far, but found it a bit too large for most summer scrambling and rock climbing trips.
  2. Comfort. A brilliant back system – the kind of thing we’re used to seeing on multi-day backpacking rucksacks. Very comfortable waist belt too, though a little cumbersome when wearing a harness. I found the chest strap to be a little too short for use when wearing bulky winter clothing.
  3. Functionality in bad weather. Generally very easy to use in all weather conditions. The Mountain Attack features big buckles, big zips, big everything. All of which is reflected in the overall weight of the sack of course. I did find the side-entry zip to the rucksack bottom compartment a little stiff, but as this is the only sack in this test to have a bottom compartment, it’s a little unfair to count this as a negative. I found the bottom compartment to be ideal for carrying a rope, or a helmet for climbing, or a stove and fuel for multi-day trips.
  4. Use across a range of activities. I used the Mountain Attack for winter mountaineering, rock climbing, scrambling, and summer backpacking, and found it served well for all of them. It is a large sack for summer work though, if you’re not carrying that much gear or clothing. The gear loops on the waist belt are good quality, as is everything else on this sack.
  5. Design. Looks like a small backpacking sack, until you look closer and see all the technical mountain-gear fixings. It can look a bit like a sack of spuds when not fully loaded though.
  6. Weight. 1.53kg
  7. Value. RRP – £100.
  8. Outstanding features. Very comfortable, lots of features, and easy to use in all weathers.
  9. Let-down features. Heavy and cumbersome for summer mountain rock days, but great for most other activities.


Force Ten Alpine 45

  1. Practicality. At 45l I found this sack to be the perfect size for a wide range of activities. I’ve used the Alpine 45 extensively for mountain walking, winter mountaineering, rock climbing and scrambling, and have to say that I find it hard to NOT take this sack when I’m heading for the hills.
  2. Comfort. At first sight, a very simple back, shoulder and waist system, but easily the most comfortable pack out of the four tested here. The shoulder straps are very soft and ergonomically designs so they just fit perfectly every time.
  3. Functionality in bad weather. No faff at all. A single big void for all your kit, with a water resistant zip at the top, and that’s it. The sack’s material is 500D Cordura which benefits from a hydrostatic head of 1000mm, making this a superb, water resistant pack in any weather. That said, open the zip and snow and spindrift will fill the cavity, so I still use rucksack liners and pack dividers to keep everything inside dry.
  4. Use across a range of activities. The Force Ten Alpine 45 has very quickly become my rucksack of choice for any mountain-based activity. It’s a very simple design as a sack, and comes with a wide range of accessory straps and buckles so you can customise the pack to be whatever you want it to be. The side straps on the waist belt were good for carrying ice axe and hammer during a climb, but were a bit thick to be used as a gear rack. The chest strap was also a bit short for use with bulky clothing.
  5. Design. Clean and simple design. It’s basically a waterproof, hard-wearing sack, with a super-comfortable carrying system, and a range of accessories to carry any technical kit.
  6. Weight. 1.22kg
  7. Value. RRP – £100.
  8. Outstanding features. Waterproof, hard-wearing, and very simple to use.
  9. Let-down features. Open the zip and you’re faced with a wide cavity into which water and snow will pour! Also, chest straps are a bit too short, and there is no sensible gear racking on the waist belt.



Let’s be straight about this. Every single one of the rucksack is a winner. These are in my opinion the best 4 mountain sacks currently available. I would be a very, very happy mountaineer indeed if I only owned any one of these sacks. That said, out of the four rucksacks tested, the Force Ten Alpine 45 is my rucksack of choice in this test. I find it’s simplicity very hard to beat. For a more weighty, touring rucksack, the Lowe Alpine 45:55 would be my choice. Both the Millet Trilogy and the Osprey Mutant are up there too though, so check out all four!