We love Rohner of Switzerland wool socks. They are hard to find (or were) and we first got them through Sierra Trading Post. Their trekker socks have a super thick layer that surrounds the bottom and sides of your feet, while the top is light and breathable and the leg part is ribbed so it stays up. Super soft wool, not a bit of itch. This is their oldest variety, they have more high tech stuff too.
http://www.rohnersocks.com/en/Trekking-Socks/original-overknee.html