Smartwool Merino Base Layer 250: Warm, Moisture Wicking, Comfortable

Thru-hiking, long-distance treks, and even short weekend hikes often walk a fine line between breathtaking views and sheer exhaustion. Let’s be honest, when covering significant miles day after day, comfort isn’t a luxury; it’s a morale booster that keeps you moving forward. That’s where Smartwool Merino Base Layer 250 become indispensable.

Crafted from high-quality, warm Merino wool, these base layers feel incredibly soft against the skin. Their moisture-wicking and odor-resistant properties are a game-changer. I typically use them for evening comfort around camp and as sleepwear, effectively replacing a sleeping bag liner and boosting the warmth rating of my backpack.

When temperatures truly drop, I’ll hike in them. They form an integral part of my layering system, paired with my Mountain Hardwear Ghost Whisperer, and an outer shell like the REI Co-op Rainier Rain Jacket along with my Duer hiking pants. For trips with cold mornings but warmer afternoons, I’ll ditch the hiking pants altogether, wearing the merino base layer with running shorts over the top—a great example of multifunctional gear and a significant weight saver.

Ultimately, it’s comfort, warmth, and unrestricted movement that make these base layers shine.

Features and Specs

Smartwool’s Merino 250 base layers are an important part of my cold-weather layering system. Here is why.

• Material: 100% Merino wool, 250g/m² weight. This weight provides a balance of warmth and breathability.
• Warmth: Designed for cold to very cold conditions. The 250 weight offers great insulation without excessive bulk.
• Odor Resistance: Merino wool naturally resists odors, reducing the trail stink.
• Moisture Management: Merino wicks moisture away from the skin, keeping you dry and comfortable.
• Comfort: Soft, non-itchy Merino wool provides next-to-skin comfort.
• Fit: Slim fit for efficient layering.
• Sizing: Generally true to size.
• Bottom Design: Full-length leggings with a wide waistband for comfort.

Should You Buy Smartwool Merino Base Layers?

The Smartwool Merino 250 base layers are truly comfortable and perform well in a variety of cold weather activities. If you prioritize quality construction, warmth, odor resistance, and moisture management, these base layers are a worthwhile purchase. I believe they will meet or exceed your expectations. I love mine!

An extra piece of advice

I’ve had 4 different pairs of Merino Wool Base Layers. Please do not put these in the dryer! I wash mine on tap cold and hang to dry. My first pair, I quickly ruined by accidentally placing them in the dryer. They shrunk 2 sizes!

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