Norway is known for the distinct folk art designs of its knitted sweaters, with geometric snowflakes and nature motifs, but did you know that the reason they look the way they do isn’t purely aesthetic?

The clothing expert behind The Iron Snail clothing brand shares all kinds of fascinating facts about textiles on the company’s social media site, and his video about Norwegian sweaters is particularly fascinating. Anyone who has owned a traditional, authentic Norwegian sweater knows that they are warm. Not like normal sweater warm, but warmer than a full-on coat warm. But why?

Here’s the secret behind the warmth

As the video explains, Norwegians perfected the art of stranded knitting to create a sweater that’s warmer than a fur coat or a wool coat, and without all the bulk. Instead of knitting with one strand of yarn, this method uses two strands, essentially creating a double layer of wool that insulates heat incredibly well. The designs serve as a way to anchor the two........

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