Cimalp Cosmiques H Breathable Trekking Jacket review: a waterproof with serious heritage

In 1964, Ford launched the Mustang, the Beatles released A Hard Day’s Night, a Chinese team claimed the first ascent of Shishapangma and French mountain brand Cimalp was founded. Much has changed in the intervening six decades, but Ford still sells the Mustang, the Beatles are perennially popular, people still want to climb Shishapangma and Cimalp is still selling mountain gear.

Yes, Cimalp recently celebrated turning 60 and, to mark the occasion, it released its Heritage Collection. It's taken some of its most iconic garments, given them 60s-inspired colorways and added an attractive original logo patch. The patch displays the founding year, as well as a leaf – a nod to the brand’s sustainability efforts. There’s plenty going on in this space: in spring 2025, Cimalp is upgrading to an "energy self-sufficient" head office, while it’s also keeping in step with the likes of Rab and Patagonia by introducing La Réparerie, a repair workshop with the intention of keeping garments in play and out of landfill.

Named after the iconic arête on Mont Blanc’s Aiguille du Midi, the Cosmiques is a waterproof jacket that features the proprietary, PFC-free Ultrashell membrane, which Cimalp name as their most important innovation. The brand is renowned for only using its own fabrics and technologies, shunning the likes of Gore-Tex and Polartec. This helps it to control costs, as well as keeping hold of the reins when it comes to its impact of the environment.

I was delighted to receive the Heritage version of the Cosmiques to see how it would fare in the British backcountry.

First impressions

The limited-edition, navy-blue Heritage colorway of the Cimalp Cosmiques H jacket is definitely attractive. Cimalp says that the Heritage Collection pays tribute to the colors that have defined the brand. Its dark blues and reds are very French, very allez! I love it. I could well imagine Kilian Mbappé striding into a stadium wearing it. The women’s version is also attractive and continues the theme, boasting three shades of blue, with deep navy around the hood and shoulders. The non-Heritage version of the jacket is also available in twin shades of green, blue, brown and black for men, and pink, green and black for women.

First wear reveals it to be less stiff than many waterproof jackets. It’s comfortable and moves with the body – always a good start. It's true to size and has a more athletic fit than most. Nevertheless, there’s still space for fleece and down layers beneath. The term fully featured gets bandied about a lot when talking about outdoor gear but the Cosmiques certainly fits the bill with five zippered pockets, pit zips, and adjustability in the cuffs, hem and hood. Versatility was evident from the off – I could imagine wearing the Cosmiques for everything from adventurous trail running to mountaineering.

Proprietary Ultrashell fabric

The Cosmiques features the same Ultrashell waterproof membrane as the Storm Pro Trail Running Jacket that I reviewed last year. For me, this relatively robust membrane is more at home on a hiking or mountaineering jacket than it is on a running jacket. Regardless of use, it’s a proven winner in the sort of serious conditions encountered in the mountains when it comes to repelling wind and precipitation while maintaining breathability.

The 3-layer ripstop fabric boasts a hydrostatic head rating of 20,000mm. This is around about the level of waterproof protection you’d expect for a trekking jacket but not quite as rugged as a mountaineering jacket boasting Gore-Tex Pro or similar – though these tend to be heavier and more restrictive. When it comes to breathability, Ultrashell is rated at 80,000 MVP – no, not ‘Most Valuable Player’ but ‘Moisture Vapor Permeability’. This is an impressive stat and I was intrigued to see if its performance would live up to the numbers.

Features

There’s no shortage of pockets here, with four zippered compartments on the front alone, as well as one hidden in the interior. The two chest pockets are positioned to be accessible when wearing a climbing harness, though the two lower handwarmers will thus be out of action in climbing situations or when covered by a daypack's hipbelt. They're great for walks in the park though.

To let off steam when moving quickly or working hard in ascent, there are pit zips that allow you to dump heat, while the 2-way front zip can also be opened up if working up a sweat. There’s no storm guard on the exterior to shield the front zipper, a feature present in many winter waterproofs to provide an additional barrier against extreme conditions. However, the zipper is laminated and there’s a length of fabric beneath, providing reinforcement for this potential chink in the armor.

The helmet compatible hood is 3-way adjustable, with the usual two points of adjustment at the front and one at the rear. Its peak is moldable, allowing you to shape it to best cope with the prevailing conditions – a nice touch. The cuffs are shaped to provide maximum coverage and can be tightened using the Velcro tab.

On the trails

I tested the Cosmiques through the winter season, both on local walks around England’s southwest and on adventures in Scotland’s Cairngorms National Park. The latter gave me the opportunity to put the jacket through its paces in extreme conditions and a variety of situations: from soaking wet and wild trail runs to mountaineering days in Britain’s coldest mountain range.

One of my qualms when I previously tested Cimalp’s Storm Pro Jacket was that it was a little bit restrictive in terms of arm movement. The Cosmiques doesn’t suffer from this in the slightest. It’s designed with an ergonomic cut, allowing freedom of movement when climbing, coiling rope or dancing about in celebration when you reach the summit. I was pleased to find that the design is effective. I had no issues with restricted movement, whether I was scrambling, hiking or running.

It's marketed as a trekking jacket and it fits this brief with aplomb. It’s protective, functional, breathable and relatively light compared to many waterproofs. However, for me, its uses go way beyond trekking. It was an obvious choice when my climbing buddies and I were faced with the kind of wet, warm and windy conditions that make trail running a superior option than mountaineering (not to mention a safer one too).

For a long, committing backcountry run in challenging conditions, the jacket’s freedom of movement and protective shield made it a good choice – I’d sooner wear it than most running jackets on these kind of days. Faced with 50mph headwinds, the tightened hood stayed in place. Faced with volley after volley of liquid sunshine, the Ultrashell membrane held firm. Faced with a sweaty 39-year-old pushing through it all, the jacket’s breathability remained impressive.

At the other end of the spectrum, it also performed very well as a mountaineering jacket, coping with Scotland’s most frigid mountains in February. With windchill at around -8°C (17°F) on the high plateau, it kept me perfectly warm when deployed on top of a Merino base layer and Cimalp’s Whymper Technical Fleece Jacket – yes, the brand have named a fleece after one of Britain’s greatest mountaineers. All of its zip pulls and adjustment points are easy to manipulate wearing thick winter gloves too.

On the trails, it's a jacket you don’t notice you’re wearing. I mean that in the best possible way. It’s light, moves with you, keeps the wind off, fends off the rain and is easy to get on with. If you were only to own one jacket, I’d say there are few that better fit the bill than this. It’s not as featherweight as some, while others are more rugged, but for sheer versatility, the Cosmiques hits the bullseye.