These things are the Carhartt of Hiking and Climbing pants, without feeling like you're wearing a canvas bag. I took them through one of the most challenging slot canyons in Utah, spent hours pinned between and literally scraping through sandstone walls (sides, knees, butt, shins were all exposed to a lot of abuse), using them to slide and slow my slide in different places, and they're barely worse for ware. A few shredded stitches on the backside and a couple minor "scars" on the side, but zero holes and zero rips. By contrast: my long-sleeve nylon-cotton T ended up with approxiamately 25 small holes (front, sides and back), other members of my slot group literally had large holes ripped in their "hiking shorts," and my brand new Merrell hiking / climbing shoes got two holes worn in them (one for each side). Among the entire group, these pants were the only thing that got out of that canyon without holes in them.

Added bonus: they also breathed well, so they are comfortable in warm or chilly weather as you're hiking in or out. Fit around waist was good. Recommend you consider one waist size larger than normal for slots or climbing, for "crotch comfort".