The best base layers, from merino and bamboo to synthetic and hybrid tops, to keep you warm on your adventures – tested by experts
Breathable and fast-wicking, the Smartwool Women’s Classic All-Season Merino Base Layer feels oh-so-soft against the skin and can be worn as a mid layer too
A super-breathable, lightweight performance running T-shirt, the Inov-8 Base Elite Short Sleeve Base Layer 3.0 is made from recycled technical polyester yarns
Comfortable, breathable and quick drying, this T-shirt is built for the trails whether you’re moving fast or taking time to smell the roses
This pull on harnesses all the best qualities of a fleece and a base layer for a lightweight, comfortable and warm layer for hiking
Are thumb holes a sign of high performance gear, or a marketing ploy to get you to spend more money?
The midweight Arc'teryx Rho Hybrid Half Zip base layer delivers versatile warmth, waterproofing and comfort while warding off odors
Our pick of the best thermal underwear for women that combines warmth with breathability
All the latest inspiration, tips and guides to help you plan your next Advnture!