UK's Fastest Growing Trail Running Brand | Over 80,000 Orders Shipped

Meet the New Thorpe Ultra-fine Merino Baselayer

Not All Baselayers Are Created Equal

Whether you're chasing records or grinding out winter miles, the right baselayer can make or break your run.

Our brand-new Thorpe Ultra-Fine Merino Baselayer was born from the feedback of our trail community: warm when wet, soft against skin, faff-free and no chafing.

We combined 68% superfine Merino wool (17.5 microns) with 32% TENCEL™ Lyocell, a natural cellulose fibre, to create a baselayer that’s breathable, odour-resistant, moisture-wicking, and regulates temperature across all conditions.

This isn’t just elite kit for elite runners, it’s smart layering for everyone who runs trails.

WHY BASELAYERS MATTER

WITH DAN SUMMERS

We caught up with Harrier’s Technical Advisor, Dan Summers, to find out why most people are thinking about baselayers all wrong:

“A lot of runners assume baselayers are just about warmth in cold weather. But almost anything can keep you warm, even a bin bag. What really matters is how your baselayer performs when you start to sweat.”

The classic scenario? You’re grinding up a climb, body is working hard and building heat. Then you stop. You take a drink. And suddenly, you’re freezing. Your baselayer is damp, clinging to your skin, and pulling heat away from your body.

“This is the moment you need your baselayer to shine. Because sweating is inevitable, especially on the trails. What you want is clothing that can cope with that sweat, so you don’t have to constantly adjust your pace or layers just to stay comfortable.”

That’s where the Thorpe comes in.

The Merino–TENCEL™ blend offers the holy grail of baselayer performance:

✅ Wicks moisture fast

✅ Stays warm when wet

✅ Breathes to dump excess heat

✅ Soft, natural fibres for all-day comfort

“Merino is well known for staying warm when wet. TENCEL™ adds superb breathability and wicking as it pulls moisture away from your skin efficiently. Together, they trap insulating air, regulate your temperature, and reduce the risk of chafing, even when worn all day.”

ANOTHER OFTEN-OVERLOOKED DETAIL?

THE FIT.

“A baselayer that’s too tight won’t trap enough air for insulation. But have it too loose, and that warm air escapes. Thumb loops on the Thorpe help keep everything in place, sealing in warmth right to your wrists.”

Dan also highlights how thumb loops and the YKK® half zip help regulate temperature without needing to stop or strip off.

“Unzipping allows airflow directly across your skin. In wind, that moving air helps shed excess heat. It’s one of the easiest and most effective ways to adjust your temperature on the move.”

And yes, this matters for all runners

This isn’t just kit for elites. In fact, Dan argues that those mid-to-back-packers may need it more.

“If you’re out for longer, your kit has to work harder and for longer. A good baselayer helps you stay comfortable all day without constant faffing. That means fewer layers to swap, fewer stops, and more time moving well on the trail.”

THORPE ULTRA-FINE MERINO BASELAYER

KEY FEATURES

YKK® half-zip for quick ventilation

Flatlocked seams for zero chafe

Thumb loops and fold-over hand mitts

Odour-resistant, itch-free Merino–TENCEL™ blend

Abrasion & pilling-resistant

Body-mapped fit for men and women

Made in the EU

Weight: Approx 200g (Men’s Medium)

The Thorpe Ultra-Fine Merino Baselayer is trail-tested and built for every step. Keep an eye out for more details, including colourways, dropping soon!

In the meantime, make sure your layering system is dialled.

Exmoor Waterproof Jacket

Packed full of features for when the weather can be… Quite British. Comfortable, non-rustle, highly waterproof (15,000mm) and breathable (15,000g/m2).

Shop Men's Exmoor

Shop Women's Exmoor

Dartmoor Waterproof Trousers

Comfortable and practical with half leg zips and no annoying rustling.

Shop Waterproof Trousers

Lomond Insulated Trail Jacket

Super warm, lightweight, easy-stash jacket with high-loft synthetic insulation.

Shop Women's Lomond

Shop Men's Lomond


2 comments


  • John Galt

    Yes please, sign me up


  • Jerry Gadd

    Can’t wait. When will I be able to buy one?


Leave a comment


Industry Awards

Runners World, Highly Commended★★★★★

Products of outstanding quality, thoughtful design and exceptional value.

The National Running Show, Winner, Retailer of the Year Award 2024★★★★★

People's choice award at the inaugural NRS awards.

Women's Running Awards 2024, Winner★★★★★

Curbar 5L - Best Race Vest, Helvellyn Carbon PRO - Best Poles, Lomond Thermal - Best Jacket, Double Layer Socks - Best Value Socks

The Guardian, Best Christmas Gifts for Runners 2024★★★★★

The Catbells V2 Aluminium Z-Poles have made the list for their balance support.

Outdoors Magic, Outdoor 100 Gear 24/25★★★★★

The Exmoor Waterproof Jacket and the Catbells V2 Aluminium Z-Poles have made the list.

Women's Running, Winner, Reader's Choice Awards 2023★★★★★

Absolutely brilliant... kit that works. Rugged, comfortable and a good price. Harrier bundles make getting trail ready a breeze.

The Independent, Best Race Vest Comfort 2021★★★★★

Extremely comfortable, form-fitting race vest that’s thoughtfully designed and good value for money.

Outdoors Magic, Best Hydration Pack 2021★★★★★

Everything a trail runner needs, at a fraction of the cost of many of its competitors. Innovative, feature-packed made by runners, for runners.

Best Value Award, Wild Ginger Running★★★★★

The race vests and Helvellyn poles have won our Best Value Award!

Fast & Tracked Delivery

Free Royal Mail Tracked48 shipping for all UK orders over £50.

Free Returns

Free 90 Day Returns and Exchanges Using Our Fast & Tracked Royal Mail Returns Service.

Help and Advice

We are always there for you if you need help finding the perfect items or choosing the right size. Talk to us support@harrierrunfree.co.uk

x