Arc’teryx hardshells, insulated jackets, and base layers have been core to the mountain athlete’s kit for decades. Constructed of progressive, premium materials and stress-tested in the world’s harshest environments, these are pieces you can rely on when it counts. From mountaineering and alpine touring to rock climbing and hiking, every Arc’teryx jacket is designed for freedom of movement, temperature regulation, and years of durable performance.

All Arc’teryx products undergo heavy testing by the world’s mountain professionals, and as a result they solve problems that only appear after sustained use in the field. Your shell might feature pockets designed to be accessible under a harness, or a helmet-compatible StormHood™ that moves with your head for better peripheral vision. Our insulated jackets are thermomapped to provide insulation where you need it most, and even our base layers have refined seams and articulated patterning to move with you.

This attention to detail and commitment to comfort guarantees that your lightweight-breathable shirt won’t chafe at mile 20; your Merino base layer won’t trap odours on a weeklong hut trip; and your climbing pants won’t catch on your crampons. With every layer designed to minimize weight, maximize performance, and work as part of a system, you can bring less, do more, and travel lighter. The art of layering starts here.

Midlayers are designed to be worn over a base layer, with or without a shell. The job of your midlayer is to trap a layer of air around your body—often using a light but lofty material like fleece, down, or synthetic insulation. Your body heats the trapped air, and that warmth stays close to your skin, buffering the effects of the cold air outside. Most midlayers are designed to keep your core warm, which is why you’ll find many options for jackets and sweaters—but in very cold environments you may want to wear insulated pants as well.

When to wear a fleece midlayer

Fleece midlayers work by creating loft within a single layer of fabric, like the lightweight hollow-core construction featured in the Delta line (women’s, men’s) or the versatile midweight Covert line (women’s, men’s). Because of their single-layer design, fleece jackets are very breathable, but don’t block wind. Worn on their own, they can be perfect for adding a little extra warmth in calm weather and lighter activities like hiking and belaying. Worn with a shell, a fleece is a great way to add lightweight, low-profile warmth to your layering system.

When to wear a down insulated midlayer

Down is the gold standard when it comes to insulation in alpine environments. Lightweight, impossibly warm and highly compressible, it’s ideal when weight and packing space are at a premium. Down jackets like the Cerium (women’s, men’s) are made to team up with other layers, with a trim fit, minimalist cuffs, and a streamlined hood. Note that when wet, down loses its loft, so it’s important to bring a shell if you’re expecting precipitation or plan to be sweating. For that reason, down layers are best for keeping you warm in between efforts (like belays or transitions on a ski tour) rather than for all-day wear.

When to wear a synthetic insulated midlayer

Synthetic insulation sacrifices some of the light weight and packability of down, but retains more of its loft and warmth when wet—whether that’s from sweat or light precipitation—which gives synthetic jackets a much wider optimal range of use. Long-running favourites like the Atom jacket (women’s, men’s) have perfected synthetic insulation over the years by adding more insulation where you need it (around your core) and less in areas where you need to dump heat (like your armpits). With a versatile fit and a water and wind-resistant outer fabric, the Atom is a great insulation pick for higher-output activities and more adverse conditions.

Shop Men’s Insulated Jackets | Shop Women’s Insulated Jackets

Once you’ve assembled your kit, it’s time to put it into practice. Take special note of how you feel as you move through mountains. Too hot? Try removing your hood, unzipping your pits, or removing a layer altogether. Too cold? Try adding an insulation layer, pulling up your hood, or swapping your base layer for a dry one. Pay special attention to your head, neck, and hands, which heat up and cool down quickly, and can help you make micro-adjustments to your overall system as you move. With high-quality layers keeping your core warm and dry, you’ll continue to enjoy whatever activity inspires you most.