Collection: Activities - Mountaineering - Technical Underwear

Your first layer for changing conditions on the mountain

Functional underwear for high-altitude hikes sits directly against your skin and should be suited to your activity level and the temperatures. An early start, a long ascent, and a break in the wind all present different challenges. Therefore, choose the fabric weight and coverage in conjunction with your other layers. Extra-warm underwear isn’t automatically the most comfortable solution for every route.

Compare base layers by material and fit

Wool, synthetic fibers, and blends differ in moisture absorption, drying time, and care requirements. The specific composition and construction influence how the garment feels; the material name alone isn’t enough for a complete assessment. Check that the first layer fits evenly and allows for full range of motion. Seams, cuffs, and fabric folds deserve special attention where a harness, backpack, or other clothing comes into contact with them.

• Warmth requirements: Plan based on exertion level, temperature, and your personal comfort.
• Fit: Test your range of motion and check for contact points with the rest of your gear.
• Coverage: Choose sleeve and pant lengths that fit your layering system.
• Care: Check washing and drying instructions for longer trips and repeated use.

Test all layers together before the trip

Try on the base layer with your softshell pants and climbing harness. This way, you can identify any problematic cuffs or wrinkles before a long stage. Plan for a change of clothes based on duration and resupply opportunities, rather than carrying extra items without a specific need. Explore technical base layers and choose a base layer that integrates seamlessly into your high-altitude hiking gear.