I wore these socks when participating in the Cateran Yomp in Perthshire - a 54 mile 24 hour event across challenging terrain. I changed them every 4-5 hours as they became moist, and as a result did not have a single blister or hot spot on either feet - this is an absolute record for me. Whilst some credit must go to my Meindl boots, the Icebreaker merino wool socks were certainly a key enabler for success in this gruelling challenge. By far the best and most comfortable socks ever for long distance walking challenges.