Walking Boots

Silva Strive Mountain Pack 23+3 | Review

A minimalist high-volume running pack that prioritises stability, comfort, and speed

Silva’s Strive Mountain Pack 23+3 is designed first and foremost for long mountain runs, particularly those that might involve an overnight stop. It’s a pack built around the needs of mountain marathoners and fastpackers carrying ultralight kit, but I’ve found it’s also versatile enough to double as a lightweight hiking daypack.

I’ve been using it across a mix of long runs, fastpacking overnighters, and full-day hikes, and it’s left a strong impression, particularly when it comes to fit and stability.

The Top Line

A highly stable, comfortable, and well-designed pack that suits ultralight loads, but that does sacrifice durability and weather protection in pursuit of low weight.

Pros: Excellent stability, very comfortable fit, versatile capacity, fairly priced
Cons: Minimal padding, limited durability, bottle pockets could be more secure, not 100% waterproof.

Buy the Silva Strive Mountain Pack 23+3: £90 at Silvasweden.uk

How I Tested It

I’ve used the Strive Mountain Pack 23+3 on long trail runs in the Brecon Beacons (Bannau Brycheiniog), across the Wiltshire Downs, and on full-day hikes in winter conditions where extra layers and fuel were essential. I’ve also loaded it up for fastpacking, carrying a full ultralight overnight setup to see how close to its limits it could realistically be pushed.

OM editor Will using the Silva Strive Mountain Pack 23+3 in the Lake District. Photos: Dave Macfarlane

Design, Fit, and Comfort

I tested the M/L version of the pack. I’m 5 foot 10 with a 37cm torso, and for me, the fit is spot on. The pack sits quite high on the back (as a running pack should, in my opinion), with the flexible hip belt resting on my hips rather than below them, a position that feels natural and effective.

The standout feature here is stability. Thanks to the twin sliding sternum straps (which offer a touch of stretch) and the flexible hip belt, the pack hugs the torso like a glove. Whether lightly loaded or close to full capacity, it feels exceptionally well balanced. There’s very little bounce, even on steep climbs or fast descents, and Silva deserves real credit for how dialed-in this harness system feels.

Padding is minimal. The back panel consists of a removable foam insert that just about does the job. Remove it, and you save weight, but you’ll need to pack carefully to avoid anything poking into your back. I love that the foam insert can double as a sit mat on breaks. That feels very on-brand for a pack aimed at fast and light missions.

Breathability has been good. Even on long efforts in hilly terrain, I’ve had no real issues with heat build-up or discomfort.

Capacity and Storage

This is available in 17+3 and 23+3 versions. I’d say the smaller size is more suited to long days running in the mountains – those days that might require extra layers, food and safety equipment. Conversely, if you want something for overnights, or day runs in more challenging conditions, the 23+3 might be a better fit.

The 23+3 litre capacity is achieved via a roll-top design, which works very well in practice. Fully extended, it offers enough space for a dialled in ultralight camping setup plus food. Cinched down, I’ve found it equally good for just carrying a waterproof, water, and a phone.

The front bungee system does an excellent job of controlling volume, keeping loads tight and stable regardless of how much you’re carrying and the excess bungee tucks neatly away into a small garage, which helps keep things tidy.

Access is straightforward. The main compartment opens wide, making packing easy, and there’s a single small internal zipped pocket. This pocket is designed specifically to house an external battery for Silva’s Free headtorch system, allowing the battery to be worn close to the body to preserve performance in cold conditions – a smart, niche detail that reflects Silva’s mountain-running focus.

Externally, storage is well judged. Stretchy side pockets can be accessed on the move and are ideal for snacks, gloves, or a lightweight waterproof jacket. Zipped hip-belt pockets are about the size of a bag of Jelly Babies and are useful for a compass, gloves, or other small essentials.

Hydration and Carry Options

The pack is hydration-bladder compatible, with an internal sleeve, Velcro hanger, and hose loops. I personally preferred using it with soft flasks on the front of the harness. Some reviewers have criticised the security of these pockets, but in my experience, it depends on flask shape. Bottles with a pronounced shoulder stayed put reliably; smoother-sided flasks could potentially slip out. A cinch cord here would improve confidence.

There are no dedicated attachments for trekking poles or ice tools, though Z-folding poles can be stashed in the side stretch pockets. I’d say this isn’t a pack designed for technical winter hardware or carrying crampons.

Weather Protection and Durability

Silva describes the fabric as “weather proof”, which feels fair, but it’s not waterproof. It’ll handle light to moderate rain, but in prolonged or heavy conditions, I’ve always used dry bags inside to protect my kit. The fabric dries relatively quickly, but I wouldn’t rely on it alone to keep gear dry.

Durability is perhaps the biggest caveat. The fabric is thin and clearly chosen to keep weight down. It’s fine for trail running and careful use, but this isn’t a pack you’d want to abuse or scrape through rough terrain regularly. It feels minimalist rather than bombproof.

Real-World Load Carrying

For testing, I’ve carried everything from minimal running loads to a full fastpacking setup, including a Therm-a-Rest NeoAir UberLite sleeping mat, Lifesystems Solo Peak tent, Therm-a-rest quilt, Jetboil Stash stove, fuel, food, and a warm layer.

At that upper end, it’s a squeeze. You need genuinely ultralight kit and good packing discipline. Used that way, though, the pack remains stable and comfortable, which is impressive.

Verdict

The Silva Strive Mountain Pack 23+3 is a superbly comfortable and stable fastpacking pack. Its biggest strength is versatility: I’ve used it for short trail runs, long winter runs requiring extra layers, multi-day fastpacking trips, and standard hiking days, and it’s handled all of those roles well.

The limitations are clear. Durability is only average, weather protection for your kit isn’t a guarantee, and I’d like to see more security for front-mounted bottles and perhaps a zipped phone pocket on the harness. But within its intended niche – mountain running and ultralight fastpacking – it performs brilliantly.

Score: 8.5/10

If you’re a mountain marathoner, fastpacker, or ultralight hiker who values comfort and stability over outright toughness, this is a pack well worth considering.

Buy the Silva Strive Mountain Pack 23+3: £90 at Silvasweden.uk