Emily Pennington/CNN Underscored

There are adventures where you’d be fine in a pair of old gym shorts, and then there are full-on outdoor romps where only the toughest pair of trekking trousers will do. For those of us who love hiking big mile days, scrambling up snaggletoothed peaks and bushwhacking through demanding terrain, there’s a pair of pants that’s a cut above the rest: Fjallraven’s Keb Trousers.

Made with the brand’s proprietary G-1000 fabric (a blend of 65% polyester, 35% organic cotton and a coating of waterproof Greenland Wax), which is PFC-free, the Keb Trousers have been recommended to me by numerous professional mountain guides throughout the years, and I finally got a pair for myself to see if they live up to the hype.

The short answer? They absolutely do. I’ve traveled way above the tree line in Rocky Mountain National Park, gone leaf peeping in chilly fall weather and tracked gorillas in Uganda with Abercrombie & Kent in these bad boys, and, apart from a little easily washed mud, they still appear good as new. Below, I’ll lay out why these are my new favorite hiking pants for shoulder season treks and frosty winter wandering.

What we liked about them

With so many features not offered by other big-name brands (think snapped, cinched leg cuffs and ventilating mesh panels), there’s a ton to love about the Keb Trousers. Here’s what really piqued my interest while I was testing them in the wilds.

Super durable

I recently had a backcountry guide at Alaska’s remote Tordrillo Mountain Lodge tell me that his Keb Trousers were the only pair of outdoor pants he’d come across that could tackle whatever he threw at them without falling apart — from guiding mountaineering trips to completing tough camp chores back at home base.

Emily Pennington/CNN Underscored

After bushwhacking for a few hours through Uganda’s Bwindi Impenetrable Forest in search of gorillas with legendary tour operator Abercrombie & Kent, I see what he means. I slogged through mud, stinging nettles and downed tree branches, but my pants (and precious leg skin) emerged dirty yet otherwise unscathed.

Roomy front pockets

Unlike many women’s hiking pants that boast stretchy side pockets (which, depending on their placement, can chafe around your thighs and knees), the Keb design has two large, burly cargo pockets on the fronts of the legs. They’re well cut enough to not make you look like She-Hulk but large enough to easily hold a smartphone, map, compass and energy bar.

Or, if you’re like me, you can stuff them with a smattering of random camera accessories like I did with my air blower and microfiber cloth when dodging black wasps and photographing mountain gorillas in the jungle.

Emily Pennington/CNN Underscored

Zippered vents

Here’s what I found really cool about the Keb Trousers: They’re made of a thicker, warmer fabric that’s perfect for cooler weather, but they offer two zippered vents on each leg for when you’re banging out a burly uphill and need a little breeze. The upper vents are lined with a mesh backing (maintaining skin protection from rough brush and bugs), while the lower ones between the knee and ankle open fully.

Great colors and styling

Sure, this note might lean into my own vanity, but sometimes I want to dress well for the marmots and various creatures I’ll likely encounter in the mountains. Like much of its lineup, Fjallraven’s Keb Trousers come in a wide variety of hip colors (eight, to be precise) and are styled with the brand’s signature two-tone look that’ll help you stand out back at the campsite or while grabbing a beer after your adventure.

What we didn’t like about them

Nothing is perfect, and while I absolutely adored Fjallraven’s Keb Trousers (and plan to bring them on many, many more adventures), here are a few things to note before buying.

No back pockets

True, not having back pockets helps create a slimmer, more feminine profile when wearing these trousers, but for some, no zippered security pockets at the rear might be a deal breaker. I took a look at the men’s model as well and was surprised that they also lack back stash pockets, which is surprising, as that’s where most of my male friends choose to store their wallets.

Emily Pennington/CNN Underscored

They’re expensive

If you’re looking for a pair of PFC-free hiking or work pants that’ll last for many, many years in the toughest conditions, Fjallraven’s Keb Trousers have got your back. Unfortunately, that abrasion resistance, sustainability and longevity doesn’t come cheap. At $235, they are one of the most expensive pairs of hiking pants on the market right now.

Not ultra light

This is pretty self-explanatory, but sometimes with great durability comes great weight. The Keb Trousers aren’t nearly as bulky as a pair of snow pants, and they’re much more breathable than a pair of ski shells, but at 1 pound, 3 ounces, they’re significantly heavier than something like Outdoor Research’s Ferrosi Pants, which weigh a scant 9 ounces.

With some of that weight, you’ll get improved insulation and wind resistance, though, which is superb for cooler climates and frigid winter treks. This was ideal for climbing 13ers in Colorado’s Rocky Mountains, but if it weren’t for the pants’ vented side panels, I would have definitely overheated in the tropical Ugandan humidity.

Emily Pennington/CNN Underscored

How they compare

Like I said before, Fjallraven’s Keb Trousers ($235) are a premium product at a premium price, and as such, they come loaded with features and increased durability that few competitors can match. That being said, here are a few other great options for hiking pants that are well made and full of fun extras.

Seeking a scuff-resistant alpine pant that sheds mild weather with ease? Arc’teryx’s Gamma LT Pants ($180) are stretchy and lightweight, and they feature zippered pockets and drawstring cuffs. If you want a sturdy, part-cotton canvas work pant like the Keb but don’t want to fork over so much cash, LIVSN’s Flex Canvas Pants ($119) are a recent addition to the outdoor adventure scene and boast a well-made, jeans-like fit with snap cuffs for more streamlined climbing and scrambling.

If you love the timeless Swedish brand Fjallraven but don’t need something this burly, check out its much more affordable Abisko Trail Stretch Trousers ($165), which are cheaper, more lightweight, pliable and quick-drying. On a strict budget? REI Co-op’s Trailmade Pants ($70 $42) feature two-way stretch, articulated knees and UPF 50+ fabric for sunny days on the trail.

Bottom line

Though they’ll cost you a pretty penny, Fjallraven’s Keb Trousers are solid, heavy-duty hiking pants that will stand the test of time, whether you’re taking them out on mellow shoulder season treks or all-day adventures in the remote backcountry. With articulated knees (and openings to add knee pads), stretch fabric and ample pockets, they’re ideal for climbing and scrambling, but casual hikers will also love their ample pocket space, vented side panels and weather-resistant G-1000 fabric, which can be re-waterproofed by applying a coat of Greenland Wax after washing. From the high peaks of the Rockies to remote photography expeditions abroad, these hiking pants are my new favorites for demanding terrain.