You need a warm jacket when you're walking and scrambling in the high mountains–a jacket like the Mens Andean Plateau Jacket from Jack Wolfskin for example. It is designed for ambitious mountaineering and trekking trips. This high-performance fabric is exceptionally stretchy, so it's perfect for dynamic activities where plenty of freedom of movement is required. The elastane in the fabric ensures the jacket always fits comfortably–however challenging the terrain. When things get chilly up there, it keeps you warm and the fabric's soft reverse side ensures superb next-to-skin comfort.