This kind of depends on what type of climbing you’re talking about: boulder gyms, climbing walls, single-pitch crags, multi-pitch climbs or wild alpine routes? Climbing is generally best in trousers made from tough, hardwearing fabrics, like outdoor trousers, hiking pants or good pants for outdoor work. For the climbing gym and summer rock climbing, lighter, thinner stretch fabrics make the best materials for climbing pants. You’ll also see that many women climbers prefer to climb in leggings – or shorts. For outdoor climbing, it’s good to have some protection against the wind or cooler temperatures. For sports climbing and bouldering in particular, climbing pants with low-profile elasticated waists or drawstring waistbands are very comfy. These designs work particularly well under a harness.