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Looking at the Merrell Thermo Rogue 4 GTX hiking boots while hiking in the forest

The Thermo Rogue 4 GTX are incredibly comfortable, resilient hiking boots, and will protect you from whatever Mother Nature throws your way. Photo: SA

We are amidst a hiking renaissance. While the Instagram-ification of many once-secret spots has caused more than a few to bemoan the changes, with it has come a whole new population of outdoor enthusiasts seeking out nature. As a result, once must go further out to get away from it all. Thankfully the industry is catching on, and more and more hiking boots come out every year to make sure that one can get off the beaten path with ease, no matter the conditions or time of year.

Enter Merrell’s latest version of their Thermo Rogue series. Once billed as a tactical boot, the fourth iteration is now more of a hybrid of a winter boot and hiking boot. It provides the warmth and traction one needs to move over icy conditions in frigid temperatures, yet is light enough to move nimbly over the same terrain with efficiency and ease. I was lucky enough to be one of the first to try it out and see how well it measures up to the other hiking boots out on the market today, and to find out what makes it special and unique.

Merrell Thermo Rogue 4 GTX: First Impressions

Pros Cons
Lightweight Synthetic materials make no mention of sustainability
Primaloft insulation Limited color options
Arctic Grip outsoles

the merrell thermo rogue 4 gtx hiking boots

When unpacking the boots, one has to make note of the design. I tried the pair in Tahoe/Tangerine colors, which to be honest, is a bit flashy for my tastes. But as the old adage says, you can’t judge a book by its cover. You must also not judge a pair of hiking boots by its colorway, and perhaps this old dog could use a bit of a fresh look. Fortunately they do offer a model on the exact opposite end of the spectrum, and one can also get the boots in all black if that better suits your style.

Handling the boot, I noticed the all-synthetic upper material, which helps keep this on the lighter side despite its burly construction and insulating layer. The synthetic materials are 100% vegan, which can be an important buying decision for many. Either way, the boot is well-made, as one would expect with one of the world’s leading hiking boot makers.

But it was in trying the boots on where they really shine. Not too many hiking boots offer instant comfort, but these felt great on first lace up. As I started to walk around I felt a responsive footbed that had ideal support, and the lacing placement felt ideal to hold my foot in place. Continuing onto a hike, the boot stayed tight throughout, and surprisingly did not have any discomfort associated with larger boots on their maiden voyage.

merrell thermo rogue 4

The all-black colorway will be a welcome option for many. Photo: Merrell

Notable Features of the Thermo Rogue 4 GTX

Insulation: As this is a hiking boot intended for winter and cold weather use, it comes with 200g PrimaLoft insulation that does not add significant bulk to the product. What the insulation does do, however, is give a nice fit all around that shapes to the foot. PrimaLoft is one of our favorites due to its great warmth, yet still holds enough breathability to not cook your foot inside. This is especially important on difficult hikes when the blood is flowing. Yet my feet never felt too warm while hiking, and when stopping for a breather the insulation kept feet warm throughout.

Vibram Arctic Grip Outsole: The Vibram Arctic Grip outsole is designed specifically for the rigors of winter use. Just as winter tires are made of a specific compound for driving on snow and ice, so is the rubber on these soles meant to hold up better in icy and snowy conditions. It’s not just marketing fluff. The combination of the lug design and rubber compound make for exceptional traction in freezing conditions.

GORE-TEX lining: The gold standard for waterproofing and breathability is part of these boots, allowing for protection from wet conditions that still gives room to breathe. For those who have had a pair of GORE-TEX hiking boots, you know that not much comes close when it comes to protection from the elements while at the same time preventing the inside turning into a sweat-filled oven.

A front-on closeup view of the Merrell Thermo Rogue 4 GTX hiking boots in the forest

Ready for whatever adventures you can muster up. Photo: SA


As mentioned before, the fact that there are only two color options on opposite ends of the spectrum make them difficult to wear for other uses than hiking. But these boots are so specialized that it’s likely you know what you’re getting into by getting these boots. This is definitely not a one-boot-to-rule-them-all type of boot. For that we recommend the tried-and-true Moab 3 Thermo which has a bit more versatility but still can cross over for winter use.

While it’s been so far so good with these boots, there’s a bit of uncertainty for how long the synthetic materials will hold up in the long run. Merrell has addressed the main wear points with reinforcements, so in theory they should hold up for quite a long time, but since it’s not a proven combination of material, there’s a chance it won’t hold up the same way a leather boot might, for example. I’ll keep this page updated if anything changes, though and let you know how a winter of heavy use translates to durability.

a studio shot of the merrell thermo rogue 4 gtx hiking boots on a pile of rocks

The style is as unique as the conditions you can put them through. Photo: Merrell

Final Thoughts

The Merrell Thermo Rogue 4 GTX is a high performance winter hiking boot. It’s very specialized for winter travel, yet you don’t need sub-zero conditions thanks to the breathability of the PrimaLoft and Gore-Tex construction. With premium rubber in the Vibram Arctic Grip underfoot, there is better traction than most when things get icy and slippery. It’s probably not going to be the only hiking boot you own if you want a boot for year-round adventures, but then again not much would hold up in every type of scenario. If you’re planning on doing some winter hikes and want exceptional comfort, support and traction, these hiking boots are well worth the price.

Buy Thermo Rogue 4 GTX on Merrell

Editor’s Note: For more gear reviews and features on The Inertia, click here.

a hiker in the sawtooth mountains with a scenic backdrop
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