The North Face THE NORTH FACE Men's Lightning Convertible Trouser, TNF Black, 28

If you're idea of hiking is more pacey hut-to-hut routes over undulating terrain than slow and steady treks at lower altitudes, then the Lightning Convertible Trousers are for you. Made from a nylon-elastane mix they're durable, stretchy and surprisingly soft. They're engineered with long-lasting FlashDry-XD™ technology that wicks away sweat helping to keep you dry and, in the long term, warm. And thanks to articulation at the knees, clambering up and down over rocks or steps is blissfully restriction-free. When the temperature rises, you can zip them off into shorts and keep on trekking.