Thru-Hiker Approved Base Layers

Base layers are arguably a long-distance hiker’s most versatile piece of clothing. We sleep in them, we hike in them, and since we’re always wearing them, they get washed less than they should. On top of being worn 24/7, these pieces need to keep you comfortable in a range of condition, from cold nights camping or sitting static to wicking sweat on a tough ascent… all without stinking to high heaven. Plus we need them to be packable, fit well, and be durable. With all that in mind, here are the pieces our thru-hikers wore to death and would still recommend.

Tasc Elevation Merino LS

MSRP: $98 (can be found on sale from $54)


This insanely soft, packable top is my go-to base layer. It’s extremely lightweight but not flimsy, and while I don’t go stabbing my merino garments with pointy objects, this shirt has held up really well and has yet to start stinking despite the fact that I do laundry approximately three times a year. The merino and bamboo combination wicks sweat and dries faster than a purely merino top, but keep in mind that if you work hard while wearing it, it will still take longer to dry than a synthetic garment. It’s super comfortable to sleep in because it isn’t too tight, and is by far my most packable base layer.

-Maggie Slepian

Icebreaker BodyFit 260 1/2-Zip Tech Top 

MSRP: $120, can be found on sale from $78


The Icebreaker BodyFit 260 1/2-Zip Tech Top is hands down my favorite thing to wear in colder temps. I’ve not only used it on winter backpacking excursions, but for ice climbing, and skii trips as well. Throughout every activity it has far exceeded my expectations. It keeps you warm without having to put on 10 layers, is unbelievably comfortable, and is durable. I have personally taken this base layer through multiple wringers and it still looks relatively new. The 1/2 zip is a nice option for when you get a little warmer throughout the day, and the built in “thumb holes” ensure your entire arm will stay warm well into your gloves. I personally haven’t had a sleepless on trail night due to cold temps (except for in really extreme conditions) since using this base layer.

-Colleen Goldhorn

Smartwool NTS Mid 250 Crew

MSRP: $95, can be found on sale from $65


The perfect baselayer for cold weather day trips. Smartwool’s classic 250 NTS crew is everything you need and nothing you don’t. A simple piece that’ll keep you warm and smelling surprisingly unoffensive. Best of all, this is possibly the softest 100% merino layer I own. The 250 NTS Crew has been my goto for cool weather treks all this year.
-Zach Davis

MSRP: $59


While Patagonia Capilene Lightweight is also available in a short sleeve t-shirt and long sleeve crew, I prefer the long sleeve zip-neck because I can roll up the sleeves in warmer temps and use the zipper to help regulate ventilation even when I am wearing it as a base layer. I usually wear it under a heavier, synthetic, long sleeve pullover or a button front, long sleeve, wool shirt.  When I have hiked in temperatures well below to slightly above freezing, it has helped keep me warm and wicked perspiration to the outer layer. By the end of a long hike, however, it can feel pretty damp, but not while I am hiking. As long as I have kept moving, it has never felt cold or clammy.  When I recently encountered one of those warmer days and ended up using it as an outer rather than a base layer, sleeves rolled up, necked opened, perspiration still dampened the material around my chest and especially between my back and my pack. After I stopped hiking for the day and took my pack off, the material dried before the sun went down and the lower temps of the fall evening set in.
John Edward Harris

Icebreaker Zone Shorts

MSRP: $70

Dresses and hiking skirts provide freedom of movement and great ventilation, but potentially expose all of your assets when scrambling up over boulders. The built-in shorts in skorts are not always comfortable and certainly not convenient when nature summons. The solution for the pants-optional hiker? Icebreaker Zone Shorts. These lightweight 200g stretch merino wool thigh-hugging bottoms will keep you both chaste and chafe-free! The fully gusseted semi-compression design allows for unrestricted strides and doesn’t crawl up. Plus merino wool not only insulates in colder temps, it creates a cooling effect and absorbs sweat on hot muggy days. I never suffered from dreaded butt or inner thigh chafing which I attribute, at least in part, to the performance of this protective, moisture-wicking base layer. Paired with a Purple Rain hiking skirt, my Icebreaker Zone Shorts lasted more than 1,000 miles before peak-a-boo holes forced me to replace them with exactly the same product.
Katina Daanan

The North Face Warm Long Underwear Tights

MSRP: $54, can be found on sale from $35

These are a very versatile thermal layer. Their flat seams make them comfortable for sleeping in and they dry quickly, which makes for a great base layer while hiking in subfreezing conditions. Despite being called “long underwear tights,” they look just like common leggings, so they also work well as “town clothes” on laundry day. I’ve worn them on their own for hiking and they hold up well.
-Marci Weber
Disclosure: Some of the preceding pieces were donated for the purpose of review

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